diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index e756293..0c2ecec 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.19.0"
+  ".": "0.20.0"
 }
\ No newline at end of file
diff --git a/.stats.yml b/.stats.yml
index f1de74b..e530c9b 100644
--- a/.stats.yml
+++ b/.stats.yml
@@ -1,4 +1,4 @@
 configured_endpoints: 58
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/ark%2Fark-ee4b9d190e3aaa146b08bc0ffed1c802dc353c3fdc37fc0097f2350ab3714b70.yml
-openapi_spec_hash: 0dad8b2e562ba7ce879425ab92169d85
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/ark%2Fark-06c3025bf12b191c3906b28173c9b359e24481dd2839dbf3e6dd0b80c1de3fd6.yml
+openapi_spec_hash: d8f8fb1f78579997b6381d64cba4e826
 config_hash: b70b11b10fc614f91f1c6f028b40780f
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 07afb71..b22258b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,18 @@
 # Changelog
 
+## 0.20.0 (2026-02-20)
+
+Full Changelog: [v0.19.0...v0.20.0](https://github.com/ArkHQ-io/ark-ruby/compare/v0.19.0...v0.20.0)
+
+### Features
+
+* **api:** add tenantId to send ([d443493](https://github.com/ArkHQ-io/ark-ruby/commit/d4434933efda6c1cc2cab76c52319113f67aab91))
+
+
+### Chores
+
+* update mock server docs ([e0cbedc](https://github.com/ArkHQ-io/ark-ruby/commit/e0cbedce73ed0f6dbd683cb3dc04b8aa9937a434))
+
 ## 0.19.0 (2026-02-07)
 
 Full Changelog: [v0.18.0...v0.19.0](https://github.com/ArkHQ-io/ark-ruby/compare/v0.18.0...v0.19.0)
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index eae9fa6..63eadc8 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -68,8 +68,8 @@ $ bundle exec rake
 
 Most tests require you to [set up a mock server](https://github.com/stoplightio/prism) against the OpenAPI spec to run the tests.
 
-```bash
-$ npx prism mock path/to/your/openapi.yml
+```sh
+$ ./scripts/mock
 ```
 
 ```bash
diff --git a/Gemfile.lock b/Gemfile.lock
index 346b817..c862a16 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -11,7 +11,7 @@ GIT
 PATH
   remote: .
   specs:
-    ark-email (0.19.0)
+    ark-email (0.20.0)
       cgi
       connection_pool
 
diff --git a/README.md b/README.md
index 641bcd0..2209923 100644
--- a/README.md
+++ b/README.md
@@ -26,7 +26,7 @@ To use this gem, install via Bundler by adding the following to your application
 <!-- x-release-please-start-version -->
 
 ```ruby
-gem "ark-email", "~> 0.19.0"
+gem "ark-email", "~> 0.20.0"
 ```
 
 <!-- x-release-please-end -->
diff --git a/lib/ark_email/models/email_list_response.rb b/lib/ark_email/models/email_list_response.rb
index 3a6b4aa..528579f 100644
--- a/lib/ark_email/models/email_list_response.rb
+++ b/lib/ark_email/models/email_list_response.rb
@@ -33,6 +33,12 @@ class EmailListResponse < ArkEmail::Internal::Type::BaseModel
       #   @return [String]
       required :subject, String
 
+      # @!attribute tenant_id
+      #   The tenant ID this email belongs to
+      #
+      #   @return [String]
+      required :tenant_id, String, api_name: :tenantId
+
       # @!attribute timestamp
       #
       #   @return [Float]
@@ -53,7 +59,7 @@ class EmailListResponse < ArkEmail::Internal::Type::BaseModel
       #   @return [String, nil]
       optional :tag, String
 
-      # @!method initialize(id:, from:, status:, subject:, timestamp:, timestamp_iso:, to:, tag: nil)
+      # @!method initialize(id:, from:, status:, subject:, tenant_id:, timestamp:, timestamp_iso:, to:, tag: nil)
       #   Some parameter documentations has been truncated, see
       #   {ArkEmail::Models::EmailListResponse} for more details.
       #
@@ -65,6 +71,8 @@ class EmailListResponse < ArkEmail::Internal::Type::BaseModel
       #
       #   @param subject [String]
       #
+      #   @param tenant_id [String] The tenant ID this email belongs to
+      #
       #   @param timestamp [Float]
       #
       #   @param timestamp_iso [Time]
diff --git a/lib/ark_email/models/email_retrieve_deliveries_response.rb b/lib/ark_email/models/email_retrieve_deliveries_response.rb
index 22708a3..aa4519c 100644
--- a/lib/ark_email/models/email_retrieve_deliveries_response.rb
+++ b/lib/ark_email/models/email_retrieve_deliveries_response.rb
@@ -71,7 +71,13 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [Symbol, ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Status]
         required :status, enum: -> { ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Status }
 
-        # @!method initialize(id:, can_retry_manually:, deliveries:, retry_state:, status:)
+        # @!attribute tenant_id
+        #   The tenant ID this email belongs to
+        #
+        #   @return [String]
+        required :tenant_id, String, api_name: :tenantId
+
+        # @!method initialize(id:, can_retry_manually:, deliveries:, retry_state:, status:, tenant_id:)
         #   Some parameter documentations has been truncated, see
         #   {ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data} for more details.
         #
@@ -84,6 +90,8 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @param retry_state [ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::RetryState, nil] Information about the current retry state of a message that is queued for delive
         #
         #   @param status [Symbol, ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Status] Current message status (lowercase). Possible values:
+        #
+        #   @param tenant_id [String] The tenant ID this email belongs to
 
         class Delivery < ArkEmail::Internal::Type::BaseModel
           # @!attribute id
diff --git a/lib/ark_email/models/email_retrieve_response.rb b/lib/ark_email/models/email_retrieve_response.rb
index e3432ac..fd843ce 100644
--- a/lib/ark_email/models/email_retrieve_response.rb
+++ b/lib/ark_email/models/email_retrieve_response.rb
@@ -63,6 +63,12 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [String]
         required :subject, String
 
+        # @!attribute tenant_id
+        #   The tenant ID this email belongs to
+        #
+        #   @return [String]
+        required :tenant_id, String, api_name: :tenantId
+
         # @!attribute timestamp
         #   Unix timestamp when the email was sent
         #
@@ -150,7 +156,7 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [String, nil]
         optional :tag, String
 
-        # @!method initialize(id:, from:, scope:, status:, subject:, timestamp:, timestamp_iso:, to:, activity: nil, attachments: nil, deliveries: nil, headers: nil, html_body: nil, message_id: nil, plain_body: nil, raw_message: nil, spam: nil, spam_score: nil, tag: nil)
+        # @!method initialize(id:, from:, scope:, status:, subject:, tenant_id:, timestamp:, timestamp_iso:, to:, activity: nil, attachments: nil, deliveries: nil, headers: nil, html_body: nil, message_id: nil, plain_body: nil, raw_message: nil, spam: nil, spam_score: nil, tag: nil)
         #   Some parameter documentations has been truncated, see
         #   {ArkEmail::Models::EmailRetrieveResponse::Data} for more details.
         #
@@ -164,6 +170,8 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #
         #   @param subject [String] Email subject line
         #
+        #   @param tenant_id [String] The tenant ID this email belongs to
+        #
         #   @param timestamp [Float] Unix timestamp when the email was sent
         #
         #   @param timestamp_iso [Time] ISO 8601 formatted timestamp
diff --git a/lib/ark_email/models/email_retry_response.rb b/lib/ark_email/models/email_retry_response.rb
index 3f5c9ca..f882a74 100644
--- a/lib/ark_email/models/email_retry_response.rb
+++ b/lib/ark_email/models/email_retry_response.rb
@@ -37,10 +37,18 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [String]
         required :message, String
 
-        # @!method initialize(id:, message:)
+        # @!attribute tenant_id
+        #   The tenant ID this email belongs to
+        #
+        #   @return [String]
+        required :tenant_id, String, api_name: :tenantId
+
+        # @!method initialize(id:, message:, tenant_id:)
         #   @param id [String] Email identifier (token)
         #
         #   @param message [String]
+        #
+        #   @param tenant_id [String] The tenant ID this email belongs to
       end
     end
   end
diff --git a/lib/ark_email/models/email_send_batch_params.rb b/lib/ark_email/models/email_send_batch_params.rb
index c8d975a..afb3726 100644
--- a/lib/ark_email/models/email_send_batch_params.rb
+++ b/lib/ark_email/models/email_send_batch_params.rb
@@ -18,16 +18,33 @@ class EmailSendBatchParams < ArkEmail::Internal::Type::BaseModel
       #   @return [String]
       required :from, String
 
+      # @!attribute tenant_id
+      #   The tenant ID to send this batch from. Determines which tenant's configuration
+      #   (domains, webhooks, tracking) is used.
+      #
+      #   - If your API key is scoped to a specific tenant, this must match that tenant or
+      #     be omitted.
+      #   - If your API key is org-level, specify the tenant to send from.
+      #   - If omitted, the organization's default tenant is used.
+      #
+      #   @return [String, nil]
+      optional :tenant_id, String, api_name: :tenantId, nil?: true
+
       # @!attribute idempotency_key
       #
       #   @return [String, nil]
       optional :idempotency_key, String
 
-      # @!method initialize(emails:, from:, idempotency_key: nil, request_options: {})
+      # @!method initialize(emails:, from:, tenant_id: nil, idempotency_key: nil, request_options: {})
+      #   Some parameter documentations has been truncated, see
+      #   {ArkEmail::Models::EmailSendBatchParams} for more details.
+      #
       #   @param emails [Array<ArkEmail::Models::EmailSendBatchParams::Email>]
       #
       #   @param from [String] Sender email for all messages
       #
+      #   @param tenant_id [String, nil] The tenant ID to send this batch from. Determines which tenant's
+      #
       #   @param idempotency_key [String]
       #
       #   @param request_options [ArkEmail::RequestOptions, Hash{Symbol=>Object}]
diff --git a/lib/ark_email/models/email_send_batch_response.rb b/lib/ark_email/models/email_send_batch_response.rb
index 4e9abf6..0caecae 100644
--- a/lib/ark_email/models/email_send_batch_response.rb
+++ b/lib/ark_email/models/email_send_batch_response.rb
@@ -45,6 +45,12 @@ class Data < ArkEmail::Internal::Type::BaseModel
         required :messages,
                  -> { ArkEmail::Internal::Type::HashOf[ArkEmail::Models::EmailSendBatchResponse::Data::Message] }
 
+        # @!attribute tenant_id
+        #   The tenant ID this batch was sent from
+        #
+        #   @return [String]
+        required :tenant_id, String, api_name: :tenantId
+
         # @!attribute total
         #   Total emails in the batch
         #
@@ -58,7 +64,7 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [Boolean, nil]
         optional :sandbox, ArkEmail::Internal::Type::Boolean
 
-        # @!method initialize(accepted:, failed:, messages:, total:, sandbox: nil)
+        # @!method initialize(accepted:, failed:, messages:, tenant_id:, total:, sandbox: nil)
         #   Some parameter documentations has been truncated, see
         #   {ArkEmail::Models::EmailSendBatchResponse::Data} for more details.
         #
@@ -68,6 +74,8 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #
         #   @param messages [Hash{Symbol=>ArkEmail::Models::EmailSendBatchResponse::Data::Message}] Map of recipient email to message info
         #
+        #   @param tenant_id [String] The tenant ID this batch was sent from
+        #
         #   @param total [Integer] Total emails in the batch
         #
         #   @param sandbox [Boolean] Whether this batch was sent in sandbox mode.
diff --git a/lib/ark_email/models/email_send_params.rb b/lib/ark_email/models/email_send_params.rb
index 1d16b14..30fdee0 100644
--- a/lib/ark_email/models/email_send_params.rb
+++ b/lib/ark_email/models/email_send_params.rb
@@ -105,6 +105,18 @@ class EmailSendParams < ArkEmail::Internal::Type::BaseModel
       #   @return [String, nil]
       optional :tag, String, nil?: true
 
+      # @!attribute tenant_id
+      #   The tenant ID to send this email from. Determines which tenant's configuration
+      #   (domains, webhooks, tracking) is used.
+      #
+      #   - If your API key is scoped to a specific tenant, this must match that tenant or
+      #     be omitted.
+      #   - If your API key is org-level, specify the tenant to send from.
+      #   - If omitted, the organization's default tenant is used.
+      #
+      #   @return [String, nil]
+      optional :tenant_id, String, api_name: :tenantId, nil?: true
+
       # @!attribute text
       #   Plain text body (accepts null, auto-generated from HTML if not provided).
       #   Maximum 5MB (5,242,880 characters).
@@ -117,7 +129,7 @@ class EmailSendParams < ArkEmail::Internal::Type::BaseModel
       #   @return [String, nil]
       optional :idempotency_key, String
 
-      # @!method initialize(from:, subject:, to:, attachments: nil, bcc: nil, cc: nil, headers: nil, html: nil, metadata: nil, reply_to: nil, tag: nil, text: nil, idempotency_key: nil, request_options: {})
+      # @!method initialize(from:, subject:, to:, attachments: nil, bcc: nil, cc: nil, headers: nil, html: nil, metadata: nil, reply_to: nil, tag: nil, tenant_id: nil, text: nil, idempotency_key: nil, request_options: {})
       #   Some parameter documentations has been truncated, see
       #   {ArkEmail::Models::EmailSendParams} for more details.
       #
@@ -143,6 +155,8 @@ class EmailSendParams < ArkEmail::Internal::Type::BaseModel
       #
       #   @param tag [String, nil] Tag for categorization and filtering (accepts null)
       #
+      #   @param tenant_id [String, nil] The tenant ID to send this email from. Determines which tenant's
+      #
       #   @param text [String, nil] Plain text body (accepts null, auto-generated from HTML if not provided).
       #
       #   @param idempotency_key [String]
diff --git a/lib/ark_email/models/email_send_raw_params.rb b/lib/ark_email/models/email_send_raw_params.rb
index f33f0ab..e1444c5 100644
--- a/lib/ark_email/models/email_send_raw_params.rb
+++ b/lib/ark_email/models/email_send_raw_params.rb
@@ -43,7 +43,19 @@ class EmailSendRawParams < ArkEmail::Internal::Type::BaseModel
       #   @return [Boolean, nil]
       optional :bounce, ArkEmail::Internal::Type::Boolean, nil?: true
 
-      # @!method initialize(from:, raw_message:, to:, bounce: nil, request_options: {})
+      # @!attribute tenant_id
+      #   The tenant ID to send this email from. Determines which tenant's configuration
+      #   (domains, webhooks, tracking) is used.
+      #
+      #   - If your API key is scoped to a specific tenant, this must match that tenant or
+      #     be omitted.
+      #   - If your API key is org-level, specify the tenant to send from.
+      #   - If omitted, the organization's default tenant is used.
+      #
+      #   @return [String, nil]
+      optional :tenant_id, String, api_name: :tenantId, nil?: true
+
+      # @!method initialize(from:, raw_message:, to:, bounce: nil, tenant_id: nil, request_options: {})
       #   Some parameter documentations has been truncated, see
       #   {ArkEmail::Models::EmailSendRawParams} for more details.
       #
@@ -55,6 +67,8 @@ class EmailSendRawParams < ArkEmail::Internal::Type::BaseModel
       #
       #   @param bounce [Boolean, nil] Whether this is a bounce message (accepts null)
       #
+      #   @param tenant_id [String, nil] The tenant ID to send this email from. Determines which tenant's
+      #
       #   @param request_options [ArkEmail::RequestOptions, Hash{Symbol=>Object}]
     end
   end
diff --git a/lib/ark_email/models/email_send_raw_response.rb b/lib/ark_email/models/email_send_raw_response.rb
index f622945..3555fd1 100644
--- a/lib/ark_email/models/email_send_raw_response.rb
+++ b/lib/ark_email/models/email_send_raw_response.rb
@@ -38,6 +38,12 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [Symbol, ArkEmail::Models::EmailSendRawResponse::Data::Status]
         required :status, enum: -> { ArkEmail::Models::EmailSendRawResponse::Data::Status }
 
+        # @!attribute tenant_id
+        #   The tenant ID this email was sent from
+        #
+        #   @return [String]
+        required :tenant_id, String, api_name: :tenantId
+
         # @!attribute to
         #   List of recipient addresses
         #
@@ -57,7 +63,7 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [Boolean, nil]
         optional :sandbox, ArkEmail::Internal::Type::Boolean
 
-        # @!method initialize(id:, status:, to:, message_id: nil, sandbox: nil)
+        # @!method initialize(id:, status:, tenant_id:, to:, message_id: nil, sandbox: nil)
         #   Some parameter documentations has been truncated, see
         #   {ArkEmail::Models::EmailSendRawResponse::Data} for more details.
         #
@@ -65,6 +71,8 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #
         #   @param status [Symbol, ArkEmail::Models::EmailSendRawResponse::Data::Status] Current delivery status
         #
+        #   @param tenant_id [String] The tenant ID this email was sent from
+        #
         #   @param to [Array<String>] List of recipient addresses
         #
         #   @param message_id [String] SMTP Message-ID header value
diff --git a/lib/ark_email/models/email_send_response.rb b/lib/ark_email/models/email_send_response.rb
index b5e56ab..d9978ba 100644
--- a/lib/ark_email/models/email_send_response.rb
+++ b/lib/ark_email/models/email_send_response.rb
@@ -38,6 +38,12 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [Symbol, ArkEmail::Models::EmailSendResponse::Data::Status]
         required :status, enum: -> { ArkEmail::Models::EmailSendResponse::Data::Status }
 
+        # @!attribute tenant_id
+        #   The tenant ID this email was sent from
+        #
+        #   @return [String]
+        required :tenant_id, String, api_name: :tenantId
+
         # @!attribute to
         #   List of recipient addresses
         #
@@ -57,7 +63,7 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #   @return [Boolean, nil]
         optional :sandbox, ArkEmail::Internal::Type::Boolean
 
-        # @!method initialize(id:, status:, to:, message_id: nil, sandbox: nil)
+        # @!method initialize(id:, status:, tenant_id:, to:, message_id: nil, sandbox: nil)
         #   Some parameter documentations has been truncated, see
         #   {ArkEmail::Models::EmailSendResponse::Data} for more details.
         #
@@ -65,6 +71,8 @@ class Data < ArkEmail::Internal::Type::BaseModel
         #
         #   @param status [Symbol, ArkEmail::Models::EmailSendResponse::Data::Status] Current delivery status
         #
+        #   @param tenant_id [String] The tenant ID this email was sent from
+        #
         #   @param to [Array<String>] List of recipient addresses
         #
         #   @param message_id [String] SMTP Message-ID header value
diff --git a/lib/ark_email/resources/emails.rb b/lib/ark_email/resources/emails.rb
index 4fe64e3..e3a2e69 100644
--- a/lib/ark_email/resources/emails.rb
+++ b/lib/ark_email/resources/emails.rb
@@ -181,7 +181,7 @@ def retry_(email_id, params = {})
       # - `GET /emails/{emailId}/deliveries` - View delivery attempts
       # - `POST /emails/{emailId}/retry` - Retry failed delivery
       #
-      # @overload send_(from:, subject:, to:, attachments: nil, bcc: nil, cc: nil, headers: nil, html: nil, metadata: nil, reply_to: nil, tag: nil, text: nil, idempotency_key: nil, request_options: {})
+      # @overload send_(from:, subject:, to:, attachments: nil, bcc: nil, cc: nil, headers: nil, html: nil, metadata: nil, reply_to: nil, tag: nil, tenant_id: nil, text: nil, idempotency_key: nil, request_options: {})
       #
       # @param from [String] Body param: Sender email address. Must be from a verified domain OR use sandbox
       #
@@ -205,6 +205,8 @@ def retry_(email_id, params = {})
       #
       # @param tag [String, nil] Body param: Tag for categorization and filtering (accepts null)
       #
+      # @param tenant_id [String, nil] Body param: The tenant ID to send this email from. Determines which tenant's
+      #
       # @param text [String, nil] Body param: Plain text body (accepts null, auto-generated from HTML if not provi
       #
       # @param idempotency_key [String] Header param: Unique key for idempotent requests. If a request with this key was
@@ -238,12 +240,14 @@ def send_(params)
       #
       # **Idempotency:** Supports `Idempotency-Key` header for safe retries.
       #
-      # @overload send_batch(emails:, from:, idempotency_key: nil, request_options: {})
+      # @overload send_batch(emails:, from:, tenant_id: nil, idempotency_key: nil, request_options: {})
       #
       # @param emails [Array<ArkEmail::Models::EmailSendBatchParams::Email>] Body param
       #
       # @param from [String] Body param: Sender email for all messages
       #
+      # @param tenant_id [String, nil] Body param: The tenant ID to send this batch from. Determines which tenant's
+      #
       # @param idempotency_key [String] Header param: Unique key for idempotent requests. If a request with this key was
       #
       # @param request_options [ArkEmail::RequestOptions, Hash{Symbol=>Object}, nil]
@@ -274,7 +278,7 @@ def send_batch(params)
       # message (with headers like From, To, Subject, Content-Type, followed by a blank
       # line and the body) must be encoded to base64 before sending.
       #
-      # @overload send_raw(from:, raw_message:, to:, bounce: nil, request_options: {})
+      # @overload send_raw(from:, raw_message:, to:, bounce: nil, tenant_id: nil, request_options: {})
       #
       # @param from [String] Sender email address. Must be from a verified domain.
       #
@@ -284,6 +288,8 @@ def send_batch(params)
       #
       # @param bounce [Boolean, nil] Whether this is a bounce message (accepts null)
       #
+      # @param tenant_id [String, nil] The tenant ID to send this email from. Determines which tenant's
+      #
       # @param request_options [ArkEmail::RequestOptions, Hash{Symbol=>Object}, nil]
       #
       # @return [ArkEmail::Models::EmailSendRawResponse]
diff --git a/lib/ark_email/version.rb b/lib/ark_email/version.rb
index bad5e57..c81ac2e 100644
--- a/lib/ark_email/version.rb
+++ b/lib/ark_email/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module ArkEmail
-  VERSION = "0.19.0"
+  VERSION = "0.20.0"
 end
diff --git a/rbi/ark_email/models/email_list_response.rbi b/rbi/ark_email/models/email_list_response.rbi
index fd4a5b9..d08a44a 100644
--- a/rbi/ark_email/models/email_list_response.rbi
+++ b/rbi/ark_email/models/email_list_response.rbi
@@ -32,6 +32,10 @@ module ArkEmail
       sig { returns(String) }
       attr_accessor :subject
 
+      # The tenant ID this email belongs to
+      sig { returns(String) }
+      attr_accessor :tenant_id
+
       sig { returns(Float) }
       attr_accessor :timestamp
 
@@ -53,6 +57,7 @@ module ArkEmail
           from: String,
           status: ArkEmail::Models::EmailListResponse::Status::OrSymbol,
           subject: String,
+          tenant_id: String,
           timestamp: Float,
           timestamp_iso: Time,
           to: String,
@@ -73,6 +78,8 @@ module ArkEmail
         # - `held` - Held for manual review
         status:,
         subject:,
+        # The tenant ID this email belongs to
+        tenant_id:,
         timestamp:,
         timestamp_iso:,
         to:,
@@ -87,6 +94,7 @@ module ArkEmail
             from: String,
             status: ArkEmail::Models::EmailListResponse::Status::TaggedSymbol,
             subject: String,
+            tenant_id: String,
             timestamp: Float,
             timestamp_iso: Time,
             to: String,
diff --git a/rbi/ark_email/models/email_retrieve_deliveries_response.rbi b/rbi/ark_email/models/email_retrieve_deliveries_response.rbi
index f492ae6..cdf935f 100644
--- a/rbi/ark_email/models/email_retrieve_deliveries_response.rbi
+++ b/rbi/ark_email/models/email_retrieve_deliveries_response.rbi
@@ -118,6 +118,10 @@ module ArkEmail
         end
         attr_accessor :status
 
+        # The tenant ID this email belongs to
+        sig { returns(String) }
+        attr_accessor :tenant_id
+
         sig do
           params(
             id: String,
@@ -131,7 +135,8 @@ module ArkEmail
                 ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::RetryState::OrHash
               ),
             status:
-              ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Status::OrSymbol
+              ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Status::OrSymbol,
+            tenant_id: String
           ).returns(T.attached_class)
         end
         def self.new(
@@ -155,7 +160,9 @@ module ArkEmail
           # - `hardfail` - Permanent failure, will not retry
           # - `held` - Held for manual review (suppression list, etc.)
           # - `bounced` - Bounced by recipient server
-          status:
+          status:,
+          # The tenant ID this email belongs to
+          tenant_id:
         )
         end
 
@@ -173,7 +180,8 @@ module ArkEmail
                   ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::RetryState
                 ),
               status:
-                ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Status::TaggedSymbol
+                ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Status::TaggedSymbol,
+              tenant_id: String
             }
           )
         end
diff --git a/rbi/ark_email/models/email_retrieve_response.rbi b/rbi/ark_email/models/email_retrieve_response.rbi
index 35e4865..07b5a49 100644
--- a/rbi/ark_email/models/email_retrieve_response.rbi
+++ b/rbi/ark_email/models/email_retrieve_response.rbi
@@ -94,6 +94,10 @@ module ArkEmail
         sig { returns(String) }
         attr_accessor :subject
 
+        # The tenant ID this email belongs to
+        sig { returns(String) }
+        attr_accessor :tenant_id
+
         # Unix timestamp when the email was sent
         sig { returns(Float) }
         attr_accessor :timestamp
@@ -230,6 +234,7 @@ module ArkEmail
             status:
               ArkEmail::Models::EmailRetrieveResponse::Data::Status::OrSymbol,
             subject: String,
+            tenant_id: String,
             timestamp: Float,
             timestamp_iso: Time,
             to: String,
@@ -271,6 +276,8 @@ module ArkEmail
           status:,
           # Email subject line
           subject:,
+          # The tenant ID this email belongs to
+          tenant_id:,
           # Unix timestamp when the email was sent
           timestamp:,
           # ISO 8601 formatted timestamp
@@ -313,6 +320,7 @@ module ArkEmail
               status:
                 ArkEmail::Models::EmailRetrieveResponse::Data::Status::TaggedSymbol,
               subject: String,
+              tenant_id: String,
               timestamp: Float,
               timestamp_iso: Time,
               to: String,
diff --git a/rbi/ark_email/models/email_retry_response.rbi b/rbi/ark_email/models/email_retry_response.rbi
index 7b0d4bc..2149c44 100644
--- a/rbi/ark_email/models/email_retry_response.rbi
+++ b/rbi/ark_email/models/email_retry_response.rbi
@@ -66,15 +66,27 @@ module ArkEmail
         sig { returns(String) }
         attr_accessor :message
 
-        sig { params(id: String, message: String).returns(T.attached_class) }
+        # The tenant ID this email belongs to
+        sig { returns(String) }
+        attr_accessor :tenant_id
+
+        sig do
+          params(id: String, message: String, tenant_id: String).returns(
+            T.attached_class
+          )
+        end
         def self.new(
           # Email identifier (token)
           id:,
-          message:
+          message:,
+          # The tenant ID this email belongs to
+          tenant_id:
         )
         end
 
-        sig { override.returns({ id: String, message: String }) }
+        sig do
+          override.returns({ id: String, message: String, tenant_id: String })
+        end
         def to_hash
         end
       end
diff --git a/rbi/ark_email/models/email_send_batch_params.rbi b/rbi/ark_email/models/email_send_batch_params.rbi
index 48e1d74..00a8f1d 100644
--- a/rbi/ark_email/models/email_send_batch_params.rbi
+++ b/rbi/ark_email/models/email_send_batch_params.rbi
@@ -18,6 +18,16 @@ module ArkEmail
       sig { returns(String) }
       attr_accessor :from
 
+      # The tenant ID to send this batch from. Determines which tenant's configuration
+      # (domains, webhooks, tracking) is used.
+      #
+      # - If your API key is scoped to a specific tenant, this must match that tenant or
+      #   be omitted.
+      # - If your API key is org-level, specify the tenant to send from.
+      # - If omitted, the organization's default tenant is used.
+      sig { returns(T.nilable(String)) }
+      attr_accessor :tenant_id
+
       sig { returns(T.nilable(String)) }
       attr_reader :idempotency_key
 
@@ -28,6 +38,7 @@ module ArkEmail
         params(
           emails: T::Array[ArkEmail::EmailSendBatchParams::Email::OrHash],
           from: String,
+          tenant_id: T.nilable(String),
           idempotency_key: String,
           request_options: ArkEmail::RequestOptions::OrHash
         ).returns(T.attached_class)
@@ -36,6 +47,14 @@ module ArkEmail
         emails:,
         # Sender email for all messages
         from:,
+        # The tenant ID to send this batch from. Determines which tenant's configuration
+        # (domains, webhooks, tracking) is used.
+        #
+        # - If your API key is scoped to a specific tenant, this must match that tenant or
+        #   be omitted.
+        # - If your API key is org-level, specify the tenant to send from.
+        # - If omitted, the organization's default tenant is used.
+        tenant_id: nil,
         idempotency_key: nil,
         request_options: {}
       )
@@ -46,6 +65,7 @@ module ArkEmail
           {
             emails: T::Array[ArkEmail::EmailSendBatchParams::Email],
             from: String,
+            tenant_id: T.nilable(String),
             idempotency_key: String,
             request_options: ArkEmail::RequestOptions
           }
diff --git a/rbi/ark_email/models/email_send_batch_response.rbi b/rbi/ark_email/models/email_send_batch_response.rbi
index 7f7ae2e..286cda9 100644
--- a/rbi/ark_email/models/email_send_batch_response.rbi
+++ b/rbi/ark_email/models/email_send_batch_response.rbi
@@ -80,6 +80,10 @@ module ArkEmail
         end
         attr_accessor :messages
 
+        # The tenant ID this batch was sent from
+        sig { returns(String) }
+        attr_accessor :tenant_id
+
         # Total emails in the batch
         sig { returns(Integer) }
         attr_accessor :total
@@ -101,6 +105,7 @@ module ArkEmail
                 Symbol,
                 ArkEmail::Models::EmailSendBatchResponse::Data::Message::OrHash
               ],
+            tenant_id: String,
             total: Integer,
             sandbox: T::Boolean
           ).returns(T.attached_class)
@@ -112,6 +117,8 @@ module ArkEmail
           failed:,
           # Map of recipient email to message info
           messages:,
+          # The tenant ID this batch was sent from
+          tenant_id:,
           # Total emails in the batch
           total:,
           # Whether this batch was sent in sandbox mode. Only present (and true) for sandbox
@@ -130,6 +137,7 @@ module ArkEmail
                   Symbol,
                   ArkEmail::Models::EmailSendBatchResponse::Data::Message
                 ],
+              tenant_id: String,
               total: Integer,
               sandbox: T::Boolean
             }
diff --git a/rbi/ark_email/models/email_send_params.rbi b/rbi/ark_email/models/email_send_params.rbi
index ff2ac1a..7233e8e 100644
--- a/rbi/ark_email/models/email_send_params.rbi
+++ b/rbi/ark_email/models/email_send_params.rbi
@@ -87,6 +87,16 @@ module ArkEmail
       sig { returns(T.nilable(String)) }
       attr_accessor :tag
 
+      # The tenant ID to send this email from. Determines which tenant's configuration
+      # (domains, webhooks, tracking) is used.
+      #
+      # - If your API key is scoped to a specific tenant, this must match that tenant or
+      #   be omitted.
+      # - If your API key is org-level, specify the tenant to send from.
+      # - If omitted, the organization's default tenant is used.
+      sig { returns(T.nilable(String)) }
+      attr_accessor :tenant_id
+
       # Plain text body (accepts null, auto-generated from HTML if not provided).
       # Maximum 5MB (5,242,880 characters).
       sig { returns(T.nilable(String)) }
@@ -112,6 +122,7 @@ module ArkEmail
           metadata: T.nilable(T::Hash[Symbol, String]),
           reply_to: T.nilable(String),
           tag: T.nilable(String),
+          tenant_id: T.nilable(String),
           text: T.nilable(String),
           idempotency_key: String,
           request_options: ArkEmail::RequestOptions::OrHash
@@ -170,6 +181,14 @@ module ArkEmail
         reply_to: nil,
         # Tag for categorization and filtering (accepts null)
         tag: nil,
+        # The tenant ID to send this email from. Determines which tenant's configuration
+        # (domains, webhooks, tracking) is used.
+        #
+        # - If your API key is scoped to a specific tenant, this must match that tenant or
+        #   be omitted.
+        # - If your API key is org-level, specify the tenant to send from.
+        # - If omitted, the organization's default tenant is used.
+        tenant_id: nil,
         # Plain text body (accepts null, auto-generated from HTML if not provided).
         # Maximum 5MB (5,242,880 characters).
         text: nil,
@@ -193,6 +212,7 @@ module ArkEmail
             metadata: T.nilable(T::Hash[Symbol, String]),
             reply_to: T.nilable(String),
             tag: T.nilable(String),
+            tenant_id: T.nilable(String),
             text: T.nilable(String),
             idempotency_key: String,
             request_options: ArkEmail::RequestOptions
diff --git a/rbi/ark_email/models/email_send_raw_params.rbi b/rbi/ark_email/models/email_send_raw_params.rbi
index ed16418..8826a18 100644
--- a/rbi/ark_email/models/email_send_raw_params.rbi
+++ b/rbi/ark_email/models/email_send_raw_params.rbi
@@ -39,12 +39,23 @@ module ArkEmail
       sig { returns(T.nilable(T::Boolean)) }
       attr_accessor :bounce
 
+      # The tenant ID to send this email from. Determines which tenant's configuration
+      # (domains, webhooks, tracking) is used.
+      #
+      # - If your API key is scoped to a specific tenant, this must match that tenant or
+      #   be omitted.
+      # - If your API key is org-level, specify the tenant to send from.
+      # - If omitted, the organization's default tenant is used.
+      sig { returns(T.nilable(String)) }
+      attr_accessor :tenant_id
+
       sig do
         params(
           from: String,
           raw_message: String,
           to: T::Array[String],
           bounce: T.nilable(T::Boolean),
+          tenant_id: T.nilable(String),
           request_options: ArkEmail::RequestOptions::OrHash
         ).returns(T.attached_class)
       end
@@ -69,6 +80,14 @@ module ArkEmail
         to:,
         # Whether this is a bounce message (accepts null)
         bounce: nil,
+        # The tenant ID to send this email from. Determines which tenant's configuration
+        # (domains, webhooks, tracking) is used.
+        #
+        # - If your API key is scoped to a specific tenant, this must match that tenant or
+        #   be omitted.
+        # - If your API key is org-level, specify the tenant to send from.
+        # - If omitted, the organization's default tenant is used.
+        tenant_id: nil,
         request_options: {}
       )
       end
@@ -80,6 +99,7 @@ module ArkEmail
             raw_message: String,
             to: T::Array[String],
             bounce: T.nilable(T::Boolean),
+            tenant_id: T.nilable(String),
             request_options: ArkEmail::RequestOptions
           }
         )
diff --git a/rbi/ark_email/models/email_send_raw_response.rbi b/rbi/ark_email/models/email_send_raw_response.rbi
index f5771bd..8c9bff9 100644
--- a/rbi/ark_email/models/email_send_raw_response.rbi
+++ b/rbi/ark_email/models/email_send_raw_response.rbi
@@ -71,6 +71,10 @@ module ArkEmail
         end
         attr_accessor :status
 
+        # The tenant ID this email was sent from
+        sig { returns(String) }
+        attr_accessor :tenant_id
+
         # List of recipient addresses
         sig { returns(T::Array[String]) }
         attr_accessor :to
@@ -95,6 +99,7 @@ module ArkEmail
             id: String,
             status:
               ArkEmail::Models::EmailSendRawResponse::Data::Status::OrSymbol,
+            tenant_id: String,
             to: T::Array[String],
             message_id: String,
             sandbox: T::Boolean
@@ -105,6 +110,8 @@ module ArkEmail
           id:,
           # Current delivery status
           status:,
+          # The tenant ID this email was sent from
+          tenant_id:,
           # List of recipient addresses
           to:,
           # SMTP Message-ID header value
@@ -121,6 +128,7 @@ module ArkEmail
               id: String,
               status:
                 ArkEmail::Models::EmailSendRawResponse::Data::Status::TaggedSymbol,
+              tenant_id: String,
               to: T::Array[String],
               message_id: String,
               sandbox: T::Boolean
diff --git a/rbi/ark_email/models/email_send_response.rbi b/rbi/ark_email/models/email_send_response.rbi
index 04d65d6..0bdd4f5 100644
--- a/rbi/ark_email/models/email_send_response.rbi
+++ b/rbi/ark_email/models/email_send_response.rbi
@@ -71,6 +71,10 @@ module ArkEmail
         end
         attr_accessor :status
 
+        # The tenant ID this email was sent from
+        sig { returns(String) }
+        attr_accessor :tenant_id
+
         # List of recipient addresses
         sig { returns(T::Array[String]) }
         attr_accessor :to
@@ -94,6 +98,7 @@ module ArkEmail
           params(
             id: String,
             status: ArkEmail::Models::EmailSendResponse::Data::Status::OrSymbol,
+            tenant_id: String,
             to: T::Array[String],
             message_id: String,
             sandbox: T::Boolean
@@ -104,6 +109,8 @@ module ArkEmail
           id:,
           # Current delivery status
           status:,
+          # The tenant ID this email was sent from
+          tenant_id:,
           # List of recipient addresses
           to:,
           # SMTP Message-ID header value
@@ -120,6 +127,7 @@ module ArkEmail
               id: String,
               status:
                 ArkEmail::Models::EmailSendResponse::Data::Status::TaggedSymbol,
+              tenant_id: String,
               to: T::Array[String],
               message_id: String,
               sandbox: T::Boolean
diff --git a/rbi/ark_email/resources/emails.rbi b/rbi/ark_email/resources/emails.rbi
index 2d83d7c..47365b7 100644
--- a/rbi/ark_email/resources/emails.rbi
+++ b/rbi/ark_email/resources/emails.rbi
@@ -180,6 +180,7 @@ module ArkEmail
           metadata: T.nilable(T::Hash[Symbol, String]),
           reply_to: T.nilable(String),
           tag: T.nilable(String),
+          tenant_id: T.nilable(String),
           text: T.nilable(String),
           idempotency_key: String,
           request_options: ArkEmail::RequestOptions::OrHash
@@ -239,6 +240,14 @@ module ArkEmail
         reply_to: nil,
         # Body param: Tag for categorization and filtering (accepts null)
         tag: nil,
+        # Body param: The tenant ID to send this email from. Determines which tenant's
+        # configuration (domains, webhooks, tracking) is used.
+        #
+        # - If your API key is scoped to a specific tenant, this must match that tenant or
+        #   be omitted.
+        # - If your API key is org-level, specify the tenant to send from.
+        # - If omitted, the organization's default tenant is used.
+        tenant_id: nil,
         # Body param: Plain text body (accepts null, auto-generated from HTML if not
         # provided). Maximum 5MB (5,242,880 characters).
         text: nil,
@@ -260,6 +269,7 @@ module ArkEmail
         params(
           emails: T::Array[ArkEmail::EmailSendBatchParams::Email::OrHash],
           from: String,
+          tenant_id: T.nilable(String),
           idempotency_key: String,
           request_options: ArkEmail::RequestOptions::OrHash
         ).returns(ArkEmail::Models::EmailSendBatchResponse)
@@ -269,6 +279,14 @@ module ArkEmail
         emails:,
         # Body param: Sender email for all messages
         from:,
+        # Body param: The tenant ID to send this batch from. Determines which tenant's
+        # configuration (domains, webhooks, tracking) is used.
+        #
+        # - If your API key is scoped to a specific tenant, this must match that tenant or
+        #   be omitted.
+        # - If your API key is org-level, specify the tenant to send from.
+        # - If omitted, the organization's default tenant is used.
+        tenant_id: nil,
         # Header param: Unique key for idempotent requests. If a request with this key was
         # already processed, the cached response is returned. Keys expire after 24 hours.
         idempotency_key: nil,
@@ -288,6 +306,7 @@ module ArkEmail
           raw_message: String,
           to: T::Array[String],
           bounce: T.nilable(T::Boolean),
+          tenant_id: T.nilable(String),
           request_options: ArkEmail::RequestOptions::OrHash
         ).returns(ArkEmail::Models::EmailSendRawResponse)
       end
@@ -312,6 +331,14 @@ module ArkEmail
         to:,
         # Whether this is a bounce message (accepts null)
         bounce: nil,
+        # The tenant ID to send this email from. Determines which tenant's configuration
+        # (domains, webhooks, tracking) is used.
+        #
+        # - If your API key is scoped to a specific tenant, this must match that tenant or
+        #   be omitted.
+        # - If your API key is org-level, specify the tenant to send from.
+        # - If omitted, the organization's default tenant is used.
+        tenant_id: nil,
         request_options: {}
       )
       end
diff --git a/sig/ark_email/models/email_list_response.rbs b/sig/ark_email/models/email_list_response.rbs
index d5a454d..7f874c0 100644
--- a/sig/ark_email/models/email_list_response.rbs
+++ b/sig/ark_email/models/email_list_response.rbs
@@ -6,6 +6,7 @@ module ArkEmail
         from: String,
         status: ArkEmail::Models::EmailListResponse::status,
         subject: String,
+        tenant_id: String,
         timestamp: Float,
         timestamp_iso: Time,
         to: String,
@@ -21,6 +22,8 @@ module ArkEmail
 
       attr_accessor subject: String
 
+      attr_accessor tenant_id: String
+
       attr_accessor timestamp: Float
 
       attr_accessor timestamp_iso: Time
@@ -36,6 +39,7 @@ module ArkEmail
         from: String,
         status: ArkEmail::Models::EmailListResponse::status,
         subject: String,
+        tenant_id: String,
         timestamp: Float,
         timestamp_iso: Time,
         to: String,
@@ -47,6 +51,7 @@ module ArkEmail
         from: String,
         status: ArkEmail::Models::EmailListResponse::status,
         subject: String,
+        tenant_id: String,
         timestamp: Float,
         timestamp_iso: Time,
         to: String,
diff --git a/sig/ark_email/models/email_retrieve_deliveries_response.rbs b/sig/ark_email/models/email_retrieve_deliveries_response.rbs
index 20e5c53..7abb383 100644
--- a/sig/ark_email/models/email_retrieve_deliveries_response.rbs
+++ b/sig/ark_email/models/email_retrieve_deliveries_response.rbs
@@ -32,7 +32,8 @@ module ArkEmail
           can_retry_manually: bool,
           deliveries: ::Array[ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Delivery],
           retry_state: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::RetryState?,
-          status: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::status
+          status: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::status,
+          tenant_id: String
         }
 
       class Data < ArkEmail::Internal::Type::BaseModel
@@ -46,12 +47,15 @@ module ArkEmail
 
         attr_accessor status: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::status
 
+        attr_accessor tenant_id: String
+
         def initialize: (
           id: String,
           can_retry_manually: bool,
           deliveries: ::Array[ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Delivery],
           retry_state: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::RetryState?,
-          status: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::status
+          status: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::status,
+          tenant_id: String
         ) -> void
 
         def to_hash: -> {
@@ -59,7 +63,8 @@ module ArkEmail
           can_retry_manually: bool,
           deliveries: ::Array[ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::Delivery],
           retry_state: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::RetryState?,
-          status: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::status
+          status: ArkEmail::Models::EmailRetrieveDeliveriesResponse::Data::status,
+          tenant_id: String
         }
 
         type delivery =
diff --git a/sig/ark_email/models/email_retrieve_response.rbs b/sig/ark_email/models/email_retrieve_response.rbs
index 69227c7..768b82c 100644
--- a/sig/ark_email/models/email_retrieve_response.rbs
+++ b/sig/ark_email/models/email_retrieve_response.rbs
@@ -33,6 +33,7 @@ module ArkEmail
           scope: ArkEmail::Models::EmailRetrieveResponse::Data::scope,
           status: ArkEmail::Models::EmailRetrieveResponse::Data::status,
           subject: String,
+          tenant_id: String,
           timestamp: Float,
           timestamp_iso: Time,
           to: String,
@@ -60,6 +61,8 @@ module ArkEmail
 
         attr_accessor subject: String
 
+        attr_accessor tenant_id: String
+
         attr_accessor timestamp: Float
 
         attr_accessor timestamp_iso: Time
@@ -122,6 +125,7 @@ module ArkEmail
           scope: ArkEmail::Models::EmailRetrieveResponse::Data::scope,
           status: ArkEmail::Models::EmailRetrieveResponse::Data::status,
           subject: String,
+          tenant_id: String,
           timestamp: Float,
           timestamp_iso: Time,
           to: String,
@@ -144,6 +148,7 @@ module ArkEmail
           scope: ArkEmail::Models::EmailRetrieveResponse::Data::scope,
           status: ArkEmail::Models::EmailRetrieveResponse::Data::status,
           subject: String,
+          tenant_id: String,
           timestamp: Float,
           timestamp_iso: Time,
           to: String,
diff --git a/sig/ark_email/models/email_retry_response.rbs b/sig/ark_email/models/email_retry_response.rbs
index 379ba38..4837058 100644
--- a/sig/ark_email/models/email_retry_response.rbs
+++ b/sig/ark_email/models/email_retry_response.rbs
@@ -26,16 +26,18 @@ module ArkEmail
         success: true
       }
 
-      type data = { id: String, message: String }
+      type data = { id: String, message: String, tenant_id: String }
 
       class Data < ArkEmail::Internal::Type::BaseModel
         attr_accessor id: String
 
         attr_accessor message: String
 
-        def initialize: (id: String, message: String) -> void
+        attr_accessor tenant_id: String
 
-        def to_hash: -> { id: String, message: String }
+        def initialize: (id: String, message: String, tenant_id: String) -> void
+
+        def to_hash: -> { id: String, message: String, tenant_id: String }
       end
     end
   end
diff --git a/sig/ark_email/models/email_send_batch_params.rbs b/sig/ark_email/models/email_send_batch_params.rbs
index 453148e..c734f3d 100644
--- a/sig/ark_email/models/email_send_batch_params.rbs
+++ b/sig/ark_email/models/email_send_batch_params.rbs
@@ -4,6 +4,7 @@ module ArkEmail
       {
         emails: ::Array[ArkEmail::EmailSendBatchParams::Email],
         from: String,
+        tenant_id: String?,
         idempotency_key: String
       }
       & ArkEmail::Internal::Type::request_parameters
@@ -16,6 +17,8 @@ module ArkEmail
 
       attr_accessor from: String
 
+      attr_accessor tenant_id: String?
+
       attr_reader idempotency_key: String?
 
       def idempotency_key=: (String) -> String
@@ -23,6 +26,7 @@ module ArkEmail
       def initialize: (
         emails: ::Array[ArkEmail::EmailSendBatchParams::Email],
         from: String,
+        ?tenant_id: String?,
         ?idempotency_key: String,
         ?request_options: ArkEmail::request_opts
       ) -> void
@@ -30,6 +34,7 @@ module ArkEmail
       def to_hash: -> {
         emails: ::Array[ArkEmail::EmailSendBatchParams::Email],
         from: String,
+        tenant_id: String?,
         idempotency_key: String,
         request_options: ArkEmail::RequestOptions
       }
diff --git a/sig/ark_email/models/email_send_batch_response.rbs b/sig/ark_email/models/email_send_batch_response.rbs
index 0b347e6..5cf1bb1 100644
--- a/sig/ark_email/models/email_send_batch_response.rbs
+++ b/sig/ark_email/models/email_send_batch_response.rbs
@@ -31,6 +31,7 @@ module ArkEmail
           accepted: Integer,
           failed: Integer,
           messages: ::Hash[Symbol, ArkEmail::Models::EmailSendBatchResponse::Data::Message],
+          tenant_id: String,
           total: Integer,
           sandbox: bool
         }
@@ -42,6 +43,8 @@ module ArkEmail
 
         attr_accessor messages: ::Hash[Symbol, ArkEmail::Models::EmailSendBatchResponse::Data::Message]
 
+        attr_accessor tenant_id: String
+
         attr_accessor total: Integer
 
         attr_reader sandbox: bool?
@@ -52,6 +55,7 @@ module ArkEmail
           accepted: Integer,
           failed: Integer,
           messages: ::Hash[Symbol, ArkEmail::Models::EmailSendBatchResponse::Data::Message],
+          tenant_id: String,
           total: Integer,
           ?sandbox: bool
         ) -> void
@@ -60,6 +64,7 @@ module ArkEmail
           accepted: Integer,
           failed: Integer,
           messages: ::Hash[Symbol, ArkEmail::Models::EmailSendBatchResponse::Data::Message],
+          tenant_id: String,
           total: Integer,
           sandbox: bool
         }
diff --git a/sig/ark_email/models/email_send_params.rbs b/sig/ark_email/models/email_send_params.rbs
index c08580b..43f0170 100644
--- a/sig/ark_email/models/email_send_params.rbs
+++ b/sig/ark_email/models/email_send_params.rbs
@@ -13,6 +13,7 @@ module ArkEmail
         metadata: ::Hash[Symbol, String]?,
         reply_to: String?,
         tag: String?,
+        tenant_id: String?,
         text: String?,
         idempotency_key: String
       }
@@ -44,6 +45,8 @@ module ArkEmail
 
       attr_accessor tag: String?
 
+      attr_accessor tenant_id: String?
+
       attr_accessor text: String?
 
       attr_reader idempotency_key: String?
@@ -62,6 +65,7 @@ module ArkEmail
         ?metadata: ::Hash[Symbol, String]?,
         ?reply_to: String?,
         ?tag: String?,
+        ?tenant_id: String?,
         ?text: String?,
         ?idempotency_key: String,
         ?request_options: ArkEmail::request_opts
@@ -79,6 +83,7 @@ module ArkEmail
         metadata: ::Hash[Symbol, String]?,
         reply_to: String?,
         tag: String?,
+        tenant_id: String?,
         text: String?,
         idempotency_key: String,
         request_options: ArkEmail::RequestOptions
diff --git a/sig/ark_email/models/email_send_raw_params.rbs b/sig/ark_email/models/email_send_raw_params.rbs
index 98cc750..2421638 100644
--- a/sig/ark_email/models/email_send_raw_params.rbs
+++ b/sig/ark_email/models/email_send_raw_params.rbs
@@ -1,7 +1,13 @@
 module ArkEmail
   module Models
     type email_send_raw_params =
-      { from: String, raw_message: String, to: ::Array[String], bounce: bool? }
+      {
+        from: String,
+        raw_message: String,
+        to: ::Array[String],
+        bounce: bool?,
+        tenant_id: String?
+      }
       & ArkEmail::Internal::Type::request_parameters
 
     class EmailSendRawParams < ArkEmail::Internal::Type::BaseModel
@@ -16,11 +22,14 @@ module ArkEmail
 
       attr_accessor bounce: bool?
 
+      attr_accessor tenant_id: String?
+
       def initialize: (
         from: String,
         raw_message: String,
         to: ::Array[String],
         ?bounce: bool?,
+        ?tenant_id: String?,
         ?request_options: ArkEmail::request_opts
       ) -> void
 
@@ -29,6 +38,7 @@ module ArkEmail
         raw_message: String,
         to: ::Array[String],
         bounce: bool?,
+        tenant_id: String?,
         request_options: ArkEmail::RequestOptions
       }
     end
diff --git a/sig/ark_email/models/email_send_raw_response.rbs b/sig/ark_email/models/email_send_raw_response.rbs
index 2ab1e07..66ba01a 100644
--- a/sig/ark_email/models/email_send_raw_response.rbs
+++ b/sig/ark_email/models/email_send_raw_response.rbs
@@ -30,6 +30,7 @@ module ArkEmail
         {
           id: String,
           status: ArkEmail::Models::EmailSendRawResponse::Data::status,
+          tenant_id: String,
           to: ::Array[String],
           message_id: String,
           sandbox: bool
@@ -40,6 +41,8 @@ module ArkEmail
 
         attr_accessor status: ArkEmail::Models::EmailSendRawResponse::Data::status
 
+        attr_accessor tenant_id: String
+
         attr_accessor to: ::Array[String]
 
         attr_reader message_id: String?
@@ -53,6 +56,7 @@ module ArkEmail
         def initialize: (
           id: String,
           status: ArkEmail::Models::EmailSendRawResponse::Data::status,
+          tenant_id: String,
           to: ::Array[String],
           ?message_id: String,
           ?sandbox: bool
@@ -61,6 +65,7 @@ module ArkEmail
         def to_hash: -> {
           id: String,
           status: ArkEmail::Models::EmailSendRawResponse::Data::status,
+          tenant_id: String,
           to: ::Array[String],
           message_id: String,
           sandbox: bool
diff --git a/sig/ark_email/models/email_send_response.rbs b/sig/ark_email/models/email_send_response.rbs
index 7426534..75ea80a 100644
--- a/sig/ark_email/models/email_send_response.rbs
+++ b/sig/ark_email/models/email_send_response.rbs
@@ -30,6 +30,7 @@ module ArkEmail
         {
           id: String,
           status: ArkEmail::Models::EmailSendResponse::Data::status,
+          tenant_id: String,
           to: ::Array[String],
           message_id: String,
           sandbox: bool
@@ -40,6 +41,8 @@ module ArkEmail
 
         attr_accessor status: ArkEmail::Models::EmailSendResponse::Data::status
 
+        attr_accessor tenant_id: String
+
         attr_accessor to: ::Array[String]
 
         attr_reader message_id: String?
@@ -53,6 +56,7 @@ module ArkEmail
         def initialize: (
           id: String,
           status: ArkEmail::Models::EmailSendResponse::Data::status,
+          tenant_id: String,
           to: ::Array[String],
           ?message_id: String,
           ?sandbox: bool
@@ -61,6 +65,7 @@ module ArkEmail
         def to_hash: -> {
           id: String,
           status: ArkEmail::Models::EmailSendResponse::Data::status,
+          tenant_id: String,
           to: ::Array[String],
           message_id: String,
           sandbox: bool
diff --git a/sig/ark_email/resources/emails.rbs b/sig/ark_email/resources/emails.rbs
index bb68cad..9821df5 100644
--- a/sig/ark_email/resources/emails.rbs
+++ b/sig/ark_email/resources/emails.rbs
@@ -41,6 +41,7 @@ module ArkEmail
         ?metadata: ::Hash[Symbol, String]?,
         ?reply_to: String?,
         ?tag: String?,
+        ?tenant_id: String?,
         ?text: String?,
         ?idempotency_key: String,
         ?request_options: ArkEmail::request_opts
@@ -49,6 +50,7 @@ module ArkEmail
       def send_batch: (
         emails: ::Array[ArkEmail::EmailSendBatchParams::Email],
         from: String,
+        ?tenant_id: String?,
         ?idempotency_key: String,
         ?request_options: ArkEmail::request_opts
       ) -> ArkEmail::Models::EmailSendBatchResponse
@@ -58,6 +60,7 @@ module ArkEmail
         raw_message: String,
         to: ::Array[String],
         ?bounce: bool?,
+        ?tenant_id: String?,
         ?request_options: ArkEmail::request_opts
       ) -> ArkEmail::Models::EmailSendRawResponse
 
diff --git a/test/ark_email/resources/emails_test.rb b/test/ark_email/resources/emails_test.rb
index b07eb19..dad8ddb 100644
--- a/test/ark_email/resources/emails_test.rb
+++ b/test/ark_email/resources/emails_test.rb
@@ -39,6 +39,7 @@ def test_list
         from: String,
         status: ArkEmail::Models::EmailListResponse::Status,
         subject: String,
+        tenant_id: String,
         timestamp: Float,
         timestamp_iso: Time,
         to: String,