diff --git a/datadog-terraform-onboarding/data.tf b/datadog-terraform-onboarding/data.tf
index a2104ab..e2d414f 100644
--- a/datadog-terraform-onboarding/data.tf
+++ b/datadog-terraform-onboarding/data.tf
@@ -38,3 +38,4 @@ data "oci_identity_domains_groups" "existing_group_in_domain" {
 data "oci_identity_domain" "domain" {
   domain_id = local.matching_domain_id
 }
+
diff --git a/datadog-terraform-onboarding/locals.tf b/datadog-terraform-onboarding/locals.tf
index b1398ed..46e76ad 100644
--- a/datadog-terraform-onboarding/locals.tf
+++ b/datadog-terraform-onboarding/locals.tf
@@ -3,6 +3,19 @@ locals {
     ownedby = "datadog"
   }
 
+  # Defined tags: parsed from user input (multiline namespace.key:value per line)
+  defined_tags_raw = [
+    for line in split("\n", var.defined_tags != null ? var.defined_tags : "") :
+    trimspace(line) if trimspace(line) != ""
+  ]
+  defined_tags = {
+    for line in local.defined_tags_raw :
+    # Format: namespace.key:value (split on first : so value can contain colons)
+    (split(":", line)[0]) => (
+      length(split(":", line)) > 1 ? join(":", slice(split(":", line), 1, length(split(":", line)))) : ""
+    )
+  }
+
   home_region_name = [
     for region in data.oci_identity_region_subscriptions.subscribed_regions.region_subscriptions : region.region_name
     if region.is_home_region
diff --git a/datadog-terraform-onboarding/main.tf b/datadog-terraform-onboarding/main.tf
index 2264877..b3a735a 100644
--- a/datadog-terraform-onboarding/main.tf
+++ b/datadog-terraform-onboarding/main.tf
@@ -179,6 +179,7 @@ module "compartment" {
   new_compartment_name  = local.new_compartment_name
   parent_compartment_id = var.tenancy_ocid
   tags                  = local.tags
+  defined_tags          = local.defined_tags
 }
 
 module "kms" {
@@ -192,6 +193,7 @@ module "kms" {
   compartment_id  = module.compartment.id
   datadog_api_key = var.datadog_api_key
   tags            = local.tags
+  defined_tags    = local.defined_tags
 }
 
 module "auth" {
@@ -201,6 +203,7 @@ module "auth" {
   user_email        = local.user_email
   tenancy_id        = var.tenancy_ocid
   tags              = local.tags
+  defined_tags      = local.defined_tags
   current_user_id   = var.current_user_ocid
   compartment_id    = module.compartment.id
   idcs_endpoint     = local.idcs_endpoint
@@ -239,6 +242,7 @@ module "integration" {
   subscribed_regions              = tolist(local.final_regions_for_stacks)
   datadog_resource_compartment_id = module.compartment.id
   logs_enabled                    = var.logs_enabled
+  defined_tags                    = local.defined_tags
 }
 
 
diff --git a/datadog-terraform-onboarding/modules/auth/main.tf b/datadog-terraform-onboarding/modules/auth/main.tf
index cf62684..3bdcc96 100644
--- a/datadog-terraform-onboarding/modules/auth/main.tf
+++ b/datadog-terraform-onboarding/modules/auth/main.tf
@@ -141,6 +141,14 @@ resource "oci_identity_domains_user" "dd_auth" {
         value = freeform_tags.value
       }
     }
+    dynamic "defined_tags" {
+      for_each = var.defined_tags
+      content {
+        namespace = split(".", defined_tags.key)[0]
+        key       = join(".", slice(split(".", defined_tags.key), 1, length(split(".", defined_tags.key))))
+        value     = defined_tags.value
+      }
+    }
   }
 }
 
@@ -165,6 +173,14 @@ resource "oci_identity_domains_group" "dd_auth" {
         value = freeform_tags.value
       }
     }
+    dynamic "defined_tags" {
+      for_each = var.defined_tags
+      content {
+        namespace = split(".", defined_tags.key)[0]
+        key       = join(".", slice(split(".", defined_tags.key), 1, length(split(".", defined_tags.key))))
+        value     = defined_tags.value
+      }
+    }
   }
 }
 
@@ -176,11 +192,13 @@ resource "oci_identity_policy" "dd_auth" {
   statements = [
     "Define tenancy usage-report as ocid1.tenancy.oc1..aaaaaaaaned4fkpkisbwjlr56u7cj63lf3wffbilvqknstgtvzub7vhqkggq",
     "Allow group id ${var.existing_group_id != null && var.existing_group_id != "" ? var.existing_group_id : oci_identity_domains_group.dd_auth[0].ocid} to read all-resources in tenancy",
+    "Allow group id ${var.existing_group_id != null && var.existing_group_id != "" ? var.existing_group_id : oci_identity_domains_group.dd_auth[0].ocid} to use tag-namespaces in tenancy",
     "Allow group id ${var.existing_group_id != null && var.existing_group_id != "" ? var.existing_group_id : oci_identity_domains_group.dd_auth[0].ocid} to manage serviceconnectors in compartment id ${var.compartment_id}",
     "Allow group id ${var.existing_group_id != null && var.existing_group_id != "" ? var.existing_group_id : oci_identity_domains_group.dd_auth[0].ocid} to manage functions-family in compartment id ${var.compartment_id} where ANY {request.permission = 'FN_FUNCTION_UPDATE', request.permission = 'FN_FUNCTION_LIST', request.permission = 'FN_APP_LIST'}",
     "Endorse group id ${var.existing_group_id != null && var.existing_group_id != "" ? var.existing_group_id : oci_identity_domains_group.dd_auth[0].ocid} to read objects in tenancy usage-report"
   ]
   freeform_tags = var.tags
+  defined_tags  = var.defined_tags
 }
 
 resource "oci_identity_domains_dynamic_resource_group" "service_connector" {
@@ -214,4 +232,5 @@ resource "oci_identity_policy" "dynamic_group" {
     "Allow dynamic-group id ${oci_identity_domains_dynamic_resource_group.forwarding_function.ocid} to read secret-bundles in compartment id ${var.compartment_id}"
   ]
   freeform_tags = var.tags
+  defined_tags  = var.defined_tags
 }
diff --git a/datadog-terraform-onboarding/modules/auth/variables.tf b/datadog-terraform-onboarding/modules/auth/variables.tf
index 675ef02..ea77ede 100644
--- a/datadog-terraform-onboarding/modules/auth/variables.tf
+++ b/datadog-terraform-onboarding/modules/auth/variables.tf
@@ -16,6 +16,12 @@ variable "tags" {
   default     = {}
 }
 
+variable "defined_tags" {
+  description = "Defined tags (flat map: Namespace.TagKey = value) for policies and Identity Domain resources"
+  type        = map(string)
+  default     = {}
+}
+
 variable "tenancy_id" {
   type        = string
   description = "OCI tenant OCID, more details can be found at https://docs.cloud.oracle.com/en-us/iaas/Content/API/Concepts/apisigningkey.htm#five"
diff --git a/datadog-terraform-onboarding/modules/compartment/main.tf b/datadog-terraform-onboarding/modules/compartment/main.tf
index 892701f..070bd92 100644
--- a/datadog-terraform-onboarding/modules/compartment/main.tf
+++ b/datadog-terraform-onboarding/modules/compartment/main.tf
@@ -21,4 +21,5 @@ resource "oci_identity_compartment" "new" {
   description    = "Compartment for Datadog generated resources"
   compartment_id = var.parent_compartment_id
   freeform_tags  = var.tags
+  defined_tags   = var.defined_tags
 }
diff --git a/datadog-terraform-onboarding/modules/compartment/variables.tf b/datadog-terraform-onboarding/modules/compartment/variables.tf
index 59978f2..5b3943b 100644
--- a/datadog-terraform-onboarding/modules/compartment/variables.tf
+++ b/datadog-terraform-onboarding/modules/compartment/variables.tf
@@ -19,4 +19,10 @@ variable "new_compartment_name" {
   description = "The name of the new compartment to create, if no compartment_id is provided"
   type        = string
   default     = "Datadog"
+}
+
+variable "defined_tags" {
+  description = "Defined tags to assign to the compartment"
+  type        = map(string)
+  default     = {}
 }
\ No newline at end of file
diff --git a/datadog-terraform-onboarding/modules/integration/locals.tf b/datadog-terraform-onboarding/modules/integration/locals.tf
index c727925..40c4e21 100644
--- a/datadog-terraform-onboarding/modules/integration/locals.tf
+++ b/datadog-terraform-onboarding/modules/integration/locals.tf
@@ -1,5 +1,4 @@
 locals {
-
   config_version = 3
   json_object = {
     data : {
@@ -19,6 +18,7 @@ locals {
         logs_config : {
           Enabled = var.logs_enabled
         }
+        defined_tags : [for k, v in var.defined_tags : "${k}:${v}"]
       }
     }
   }
diff --git a/datadog-terraform-onboarding/modules/integration/variables.tf b/datadog-terraform-onboarding/modules/integration/variables.tf
index 695eb7e..b3a2c1e 100644
--- a/datadog-terraform-onboarding/modules/integration/variables.tf
+++ b/datadog-terraform-onboarding/modules/integration/variables.tf
@@ -54,3 +54,9 @@ variable "logs_enabled" {
   description = "Indicates if logs should be enabled/disabled"
   default     = false
 }
+
+variable "defined_tags" {
+  type        = map(string)
+  description = "OCI defined tags applied to resources (namespace.key -> value). Sent to Datadog for integration config."
+  default     = {}
+}
diff --git a/datadog-terraform-onboarding/modules/kms/main.tf b/datadog-terraform-onboarding/modules/kms/main.tf
index d1b9af5..8efac43 100644
--- a/datadog-terraform-onboarding/modules/kms/main.tf
+++ b/datadog-terraform-onboarding/modules/kms/main.tf
@@ -14,6 +14,7 @@ resource "oci_kms_vault" "datadog_vault" {
   display_name   = "datadog-vault"
   vault_type     = "DEFAULT"
   freeform_tags  = var.tags
+  defined_tags   = var.defined_tags
 
   timeouts {
     create = "60m"
@@ -31,6 +32,7 @@ resource "oci_kms_key" "datadog_key" {
   }
   management_endpoint = oci_kms_vault.datadog_vault.management_endpoint
   freeform_tags       = var.tags
+  defined_tags        = var.defined_tags
 
   timeouts {
     create = "60m"
@@ -49,6 +51,7 @@ resource "oci_vault_secret" "api_key" {
     content      = base64encode(var.datadog_api_key)
   }
   freeform_tags = var.tags
+  defined_tags  = var.defined_tags
 
   timeouts {
     create = "60m"
diff --git a/datadog-terraform-onboarding/modules/kms/variables.tf b/datadog-terraform-onboarding/modules/kms/variables.tf
index 5a91bbb..c209e10 100644
--- a/datadog-terraform-onboarding/modules/kms/variables.tf
+++ b/datadog-terraform-onboarding/modules/kms/variables.tf
@@ -14,3 +14,9 @@ variable "datadog_api_key" {
   description = "The API key for sending message to datadog endpoints"
   sensitive   = true
 }
+
+variable "defined_tags" {
+  type        = map(string)
+  description = "Defined tags to assign to resources"
+  default     = {}
+}
diff --git a/datadog-terraform-onboarding/modules/regional-stacks/locals.tf b/datadog-terraform-onboarding/modules/regional-stacks/locals.tf
index 3856f40..aafd683 100644
--- a/datadog-terraform-onboarding/modules/regional-stacks/locals.tf
+++ b/datadog-terraform-onboarding/modules/regional-stacks/locals.tf
@@ -38,6 +38,6 @@ locals {
     upper(local.subnet_region_from_ocid) == var.region_key
   )
   
-  # Simple subnet selection logic: use provided OCID or create new
-  subnet_id = var.subnet_ocid != "" ? var.subnet_ocid : module.vcn[0].subnet_id[local.subnet]
+  # Simple subnet selection logic: use provided OCID or create new (subnet from our subnet submodule when we create VCN)
+  subnet_id = var.subnet_ocid != "" ? var.subnet_ocid : module.subnet[0].subnet_id[local.subnet]
 }
diff --git a/datadog-terraform-onboarding/modules/regional-stacks/main.tf b/datadog-terraform-onboarding/modules/regional-stacks/main.tf
index d0c1c6d..8fbb7c0 100644
--- a/datadog-terraform-onboarding/modules/regional-stacks/main.tf
+++ b/datadog-terraform-onboarding/modules/regional-stacks/main.tf
@@ -20,9 +20,9 @@ resource "oci_functions_function" "logs_function" {
   display_name   = "dd-logs-forwarder"
   memory_in_mbs  = "1024"
   freeform_tags  = var.tags
+  defined_tags   = var.defined_tags
   image          = local.logs_image_path
   image_digest   = length(local.image_sha_logs) > 0 ? local.image_sha_logs : null
-
 }
 
 resource "oci_functions_function" "metrics_function" {
@@ -30,6 +30,7 @@ resource "oci_functions_function" "metrics_function" {
   display_name   = "dd-metrics-forwarder"
   memory_in_mbs  = "512"
   freeform_tags  = var.tags
+  defined_tags   = var.defined_tags
   image          = local.metrics_image_path
   image_digest   = length(local.image_sha_metrics) > 0 ? local.image_sha_metrics : null
 }
@@ -40,11 +41,28 @@ module "vcn" {
   version                  = ">= 3.6.0"
   compartment_id           = var.compartment_ocid
   freeform_tags            = var.tags
+  defined_tags             = var.defined_tags
   vcn_cidrs                = ["10.0.0.0/16"]
   vcn_dns_label            = "ddvcnmodule"
   vcn_name                 = local.vcn_name
-  lockdown_default_seclist = false
+  lockdown_default_seclist  = false
+  subnets                  = {}
+
+  create_nat_gateway           = true
+  nat_gateway_display_name     = local.nat_gateway
+  create_service_gateway       = true
+  service_gateway_display_name = local.service_gateway
+}
 
+# Subnet submodule so we can pass defined_tags (upstream VCN module does not pass them to subnets).
+module "subnet" {
+  count           = var.subnet_ocid == "" ? 1 : 0
+  source          = "oracle-terraform-modules/vcn/oci//modules/subnet"
+  version         = ">= 3.6.0"
+  compartment_id  = var.compartment_ocid
+  vcn_id          = module.vcn[0].vcn_id
+  nat_route_id    = module.vcn[0].nat_route_id
+  ig_route_id     = module.vcn[0].ig_route_id
   subnets = {
     private = {
       cidr_block = "10.0.0.0/16"
@@ -52,17 +70,15 @@ module "vcn" {
       name       = local.subnet
     }
   }
-
-  create_nat_gateway           = true
-  nat_gateway_display_name     = local.nat_gateway
-  create_service_gateway       = true
-  service_gateway_display_name = local.service_gateway
+  freeform_tags = var.tags
+  defined_tags  = var.defined_tags
 }
 
 resource "oci_functions_application" "dd_function_app" {
   compartment_id = var.compartment_ocid
   display_name   = "dd-function-app"
   freeform_tags  = var.tags
+  defined_tags   = var.defined_tags
   shape          = "GENERIC_X86_ARM"
   subnet_ids = [
     local.subnet_id
diff --git a/datadog-terraform-onboarding/modules/regional-stacks/variables.tf b/datadog-terraform-onboarding/modules/regional-stacks/variables.tf
index c5ac420..0ccf877 100644
--- a/datadog-terraform-onboarding/modules/regional-stacks/variables.tf
+++ b/datadog-terraform-onboarding/modules/regional-stacks/variables.tf
@@ -51,3 +51,9 @@ variable "subnet_ocid" {
     error_message = "If provided, subnet_ocid must be a valid subnet OCID starting with: ocid1.subnet.oc[0-9]."
   }
 }
+
+variable "defined_tags" {
+  type        = map(string)
+  description = "Defined tags to assign to VCN, subnet, function app and functions."
+  default     = {}
+}
diff --git a/datadog-terraform-onboarding/regional_stack.tf b/datadog-terraform-onboarding/regional_stack.tf
index d56957d..4442522 100644
--- a/datadog-terraform-onboarding/regional_stack.tf
+++ b/datadog-terraform-onboarding/regional_stack.tf
@@ -23,6 +23,7 @@ module "regional_deployment_af_johannesburg_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -48,6 +49,7 @@ module "regional_deployment_ap_batam_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -73,6 +75,7 @@ module "regional_deployment_ap_chuncheon_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -98,6 +101,7 @@ module "regional_deployment_ap_hyderabad_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -123,6 +127,7 @@ module "regional_deployment_ap_melbourne_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -148,6 +153,7 @@ module "regional_deployment_ap_mumbai_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -173,6 +179,7 @@ module "regional_deployment_ap_osaka_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -198,6 +205,7 @@ module "regional_deployment_ap_seoul_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -223,6 +231,7 @@ module "regional_deployment_ap_singapore_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -248,6 +257,7 @@ module "regional_deployment_ap_singapore_2" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -273,6 +283,7 @@ module "regional_deployment_ap_sydney_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -298,6 +309,7 @@ module "regional_deployment_ap_tokyo_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -323,6 +335,7 @@ module "regional_deployment_ca_montreal_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -348,6 +361,7 @@ module "regional_deployment_ca_toronto_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -373,6 +387,7 @@ module "regional_deployment_eu_amsterdam_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -398,6 +413,7 @@ module "regional_deployment_eu_frankfurt_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -423,6 +439,7 @@ module "regional_deployment_eu_madrid_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -448,6 +465,7 @@ module "regional_deployment_eu_marseille_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -473,6 +491,7 @@ module "regional_deployment_eu_milan_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -498,6 +517,7 @@ module "regional_deployment_eu_paris_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -523,6 +543,7 @@ module "regional_deployment_eu_stockholm_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -548,6 +569,7 @@ module "regional_deployment_eu_zurich_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -573,6 +595,7 @@ module "regional_deployment_il_jerusalem_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -598,6 +621,7 @@ module "regional_deployment_me_abudhabi_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -623,6 +647,7 @@ module "regional_deployment_me_dubai_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -648,6 +673,7 @@ module "regional_deployment_me_jeddah_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -673,6 +699,7 @@ module "regional_deployment_me_riyadh_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -698,6 +725,7 @@ module "regional_deployment_mx_monterrey_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -723,6 +751,7 @@ module "regional_deployment_mx_queretaro_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -748,6 +777,7 @@ module "regional_deployment_sa_bogota_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -773,6 +803,7 @@ module "regional_deployment_sa_santiago_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -798,6 +829,7 @@ module "regional_deployment_sa_saopaulo_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -823,6 +855,7 @@ module "regional_deployment_sa_valparaiso_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -848,6 +881,7 @@ module "regional_deployment_sa_vinhedo_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -873,6 +907,7 @@ module "regional_deployment_uk_cardiff_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -898,6 +933,7 @@ module "regional_deployment_uk_london_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -923,6 +959,7 @@ module "regional_deployment_us_ashburn_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -948,6 +985,7 @@ module "regional_deployment_us_chicago_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -973,6 +1011,7 @@ module "regional_deployment_us_phoenix_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -998,6 +1037,7 @@ module "regional_deployment_us_sanjose_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -1023,6 +1063,7 @@ module "regional_deployment_eu_madrid_3" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
@@ -1048,6 +1089,7 @@ module "regional_deployment_eu_turin_1" {
   api_key_secret_id = local.api_key_secret_id
   home_region       = local.home_region_name
   tags              = local.tags
+  defined_tags      = local.defined_tags
 
   depends_on = [
     terraform_data.prechecks_complete,
diff --git a/datadog-terraform-onboarding/variables.tf b/datadog-terraform-onboarding/variables.tf
index 7037ba5..b050976 100644
--- a/datadog-terraform-onboarding/variables.tf
+++ b/datadog-terraform-onboarding/variables.tf
@@ -81,3 +81,9 @@ variable "user_email" {
   description = "Email address where you want OCI to send you notifications about the created user."
   default     = null
 }
+
+variable "defined_tags" {
+  type        = string
+  description = "Defined tags to apply to all created resources. One entry per line in the format namespace.key:value (e.g. CostCenter.Environment:prod). Leave blank unless your tenancy has mandatory tag defaults."
+  default     = ""
+}