diff --git a/features/language-core.feature b/features/language-core.feature
index b3d9b56a..ecab9c70 100644
--- a/features/language-core.feature
+++ b/features/language-core.feature
@@ -477,6 +477,77 @@ Feature: Manage core translation files for a WordPress install
         | nl_NL     | installed  |
     And STDERR should be empty
 
+  @require-wp-4.0
+  Scenario: Core translation update with format flag
+    Given a WP install
+    And an empty cache
+
+    When I run `wp language core update --format=json`
+    Then STDOUT should be:
+      """
+      []
+      """
+    And STDERR should be empty
+
+    When I run `wp language core update --format=csv`
+    Then STDOUT should be empty
+    And STDERR should be empty
+
+    When I run `wp language core update --format=summary`
+    Then STDOUT should contain:
+      """
+      Success: Translations are up to date.
+      """
+    And STDERR should be empty
+
+  @require-wp-6.0 @require-php-7.2
+  Scenario Outline: Core translation update with dry-run and format flag
+    Given an empty directory
+    And WP files
+    And a database
+    And I run `wp core download --version=<original> --force`
+    And wp-config.php
+    And I run `wp core install --url='localhost:8001' --title='Test' --admin_user=wpcli --admin_email=admin@example.com --admin_password=1`
+
+    When I run `wp language core install en_CA ja`
+    Then STDERR should be empty
+
+    Given I try `wp core download --version=<update> --force`
+    Then the return code should be 0
+    And I run `wp core update-db`
+
+    When I run `wp language core list --fields=language,status,update`
+    Then STDOUT should be a table containing rows:
+      | language | status    | update    |
+      | en_CA    | installed | available |
+      | ja       | installed | available |
+
+    When I run `wp language core update --dry-run --format=json`
+    Then STDOUT should be JSON containing:
+      """
+      [{"Type":"Core","Name":"WordPress","Version":"<update>"}]
+      """
+    And STDERR should be empty
+
+    When I run `wp language core update --dry-run --format=csv`
+    Then STDOUT should contain:
+      """
+      Type,Name,Version,Language
+      """
+    And STDOUT should contain:
+      """
+      Core,WordPress,<update>
+      """
+    And STDERR should be empty
+
+    When I run `wp language core update --dry-run --format=summary`
+    Then STDOUT should be empty
+    And STDERR should be empty
+
+    Examples:
+      | original | update |
+      | 6.5      | 6.6    |
+
   @require-wp-4.0
   Scenario: Install languages with different output formats
     Given a WP install
diff --git a/features/language-plugin.feature b/features/language-plugin.feature
index e24a4df2..b738af15 100644
--- a/features/language-plugin.feature
+++ b/features/language-plugin.feature
@@ -443,6 +443,119 @@ Feature: Manage plugin translation files for a WordPress install
     And STDERR should be empty
 
   @require-wp-4.0
+  Scenario: Plugin translation update with format flag
+    Given a WP install
+
+    When I run `wp plugin install hello-dolly --force`
+    Then STDERR should be empty
+
+    When I run `wp language plugin update hello-dolly --format=json`
+    Then STDOUT should be:
+      """
+      []
+      """
+    And STDERR should be empty
+
+    When I run `wp language plugin update --all --format=csv`
+    Then STDOUT should be empty
+    And STDERR should be empty
+
+    When I run `wp language plugin update --all --format=summary`
+    Then STDOUT should contain:
+      """
+      Success: Translations are up to date.
+      """
+    And STDERR should be empty
+
+  @require-wp-4.0
+  Scenario: Plugin translation update with format flag and actual updates
+    Given a WP install
+    And an empty cache
+
+    When I run `wp plugin install akismet --version=3.2 --force`
+    Then STDERR should be empty
+
+    When I run `wp language plugin install akismet de_DE`
+    Then STDERR should be empty
+
+    When I run `wp plugin install akismet --version=4.0 --force`
+    And I run `wp language plugin list akismet --fields=plugin,language,update,status`
+    Then STDOUT should be a table containing rows:
+      | plugin  | language | update    | status    |
+      | akismet | de_DE    | available | installed |
+
+    When I run `wp language plugin update akismet --format=json`
+    Then STDOUT should be JSON containing:
+      """
+      [{"slug":"akismet","language":"de_DE","status":"updated"}]
+      """
+    And STDERR should be empty
+
+    When I run `wp language plugin uninstall akismet de_DE`
+    And I run `wp plugin install akismet --version=3.2 --force`
+    And I run `wp language plugin install akismet de_DE`
+    And I run `wp plugin install akismet --version=4.0 --force`
+    And I run `wp language plugin update akismet --format=csv`
+    Then STDOUT should contain:
+      """
+      slug,language,status
+      """
+    And STDOUT should contain:
+      """
+      akismet,de_DE,updated
+      """
+    And STDERR should be empty
+
+    When I run `wp language plugin uninstall akismet de_DE`
+    And I run `wp plugin install akismet --version=3.2 --force`
+    And I run `wp language plugin install akismet de_DE`
+    And I run `wp plugin install akismet --version=4.0 --force`
+    And I run `wp language plugin update akismet --format=summary`
+    Then STDOUT should contain:
+      """
+      Success: Updated 1/1 translation.
+      """
+    And STDERR should be empty
+
+  @require-wp-4.0
+  Scenario: Plugin translation update with dry-run and format flag
+    Given a WP install
+    And an empty cache
+
+    When I run `wp plugin install akismet --version=3.2 --force`
+    Then STDERR should be empty
+
+    When I run `wp language plugin install akismet de_DE`
+    Then STDERR should be empty
+
+    When I run `wp plugin install akismet --version=4.0 --force`
+    And I run `wp language plugin list akismet --fields=plugin,language,update,status`
+    Then STDOUT should be a table containing rows:
+      | plugin  | language | update    | status    |
+      | akismet | de_DE    | available | installed |
+
+    When I run `wp language plugin update akismet --dry-run --format=json`
+    Then STDOUT should contain:
+      """
+      "Type":"Plugin"
+      """
+    And STDERR should be empty
+
+    When I run `wp language plugin update akismet --dry-run --format=csv`
+    Then STDOUT should contain:
+      """
+      Type,Name,Version,Language
+      """
+    And STDOUT should contain:
+      """
+      Plugin,"Akismet
+      """
+    And STDERR should be empty
+
+    When I run `wp language plugin update akismet --dry-run --format=summary`
+    Then STDOUT should be empty
+    And STDERR should be empty
+
   Scenario: Handle plugins with text domain different from slug
     Given a WP install
     And an empty cache
diff --git a/features/language-theme.feature b/features/language-theme.feature
index 3739e18e..cb58ea17 100644
--- a/features/language-theme.feature
+++ b/features/language-theme.feature
@@ -327,6 +327,119 @@ Feature: Manage theme translation files for a WordPress install
     And STDERR should be empty
 
   @require-wp-4.0
+  Scenario: Theme translation update with format flag
+    Given a WP install
+
+    When I try `wp theme install twentyten`
+    Then STDOUT should not be empty
+
+    When I run `wp language theme update twentyten --format=json`
+    Then STDOUT should be:
+      """
+      []
+      """
+    And STDERR should be empty
+
+    When I run `wp language theme update --all --format=csv`
+    Then STDOUT should be empty
+    And STDERR should be empty
+
+    When I run `wp language theme update --all --format=summary`
+    Then STDOUT should contain:
+      """
+      Success: Translations are up to date.
+      """
+    And STDERR should be empty
+
+  @require-wp-4.0
+  Scenario: Theme translation update with format flag and actual updates
+    Given a WP install
+    And an empty cache
+
+    When I run `wp theme install twentyfifteen --version=2.0 --force`
+    Then STDERR should be empty
+
+    When I run `wp language theme install twentyfifteen de_DE`
+    Then STDERR should be empty
+
+    When I run `wp theme install twentyfifteen --version=2.5 --force`
+    And I run `wp language theme list twentyfifteen --fields=theme,language,update,status`
+    Then STDOUT should be a table containing rows:
+      | theme         | language | update    | status    |
+      | twentyfifteen | de_DE    | available | installed |
+
+    When I run `wp language theme update twentyfifteen --format=json`
+    Then STDOUT should be JSON containing:
+      """
+      [{"slug":"twentyfifteen","language":"de_DE","status":"updated"}]
+      """
+    And STDERR should be empty
+
+    When I run `wp language theme uninstall twentyfifteen de_DE`
+    And I run `wp theme install twentyfifteen --version=2.0 --force`
+    And I run `wp language theme install twentyfifteen de_DE`
+    And I run `wp theme install twentyfifteen --version=2.5 --force`
+    And I run `wp language theme update twentyfifteen --format=csv`
+    Then STDOUT should contain:
+      """
+      slug,language,status
+      """
+    And STDOUT should contain:
+      """
+      twentyfifteen,de_DE,updated
+      """
+    And STDERR should be empty
+
+    When I run `wp language theme uninstall twentyfifteen de_DE`
+    And I run `wp theme install twentyfifteen --version=2.0 --force`
+    And I run `wp language theme install twentyfifteen de_DE`
+    And I run `wp theme install twentyfifteen --version=2.5 --force`
+    And I run `wp language theme update twentyfifteen --format=summary`
+    Then STDOUT should contain:
+      """
+      Success: Updated 1/1 translation.
+      """
+    And STDERR should be empty
+
+  @require-wp-4.0
+  Scenario: Theme translation update with dry-run and format flag
+    Given a WP install
+    And an empty cache
+
+    When I run `wp theme install twentyfifteen --version=2.0 --force`
+    Then STDERR should be empty
+
+    When I run `wp language theme install twentyfifteen de_DE`
+    Then STDERR should be empty
+
+    When I run `wp theme install twentyfifteen --version=2.5 --force`
+    And I run `wp language theme list twentyfifteen --fields=theme,language,update,status`
+    Then STDOUT should be a table containing rows:
+      | theme         | language | update    | status    |
+      | twentyfifteen | de_DE    | available | installed |
+
+    When I run `wp language theme update twentyfifteen --dry-run --format=json`
+    Then STDOUT should be JSON containing:
+      """
+      [{"Type":"Theme","Name":"Twenty Fifteen"}]
+      """
+    And STDERR should be empty
+
+    When I run `wp language theme update twentyfifteen --dry-run --format=csv`
+    Then STDOUT should contain:
+      """
+      Type,Name,Version,Language
+      """
+    And STDOUT should contain:
+      """
+      Theme,"Twenty Fifteen"
+      """
+    And STDERR should be empty
+
+    When I run `wp language theme update twentyfifteen --dry-run --format=summary`
+    Then STDOUT should be empty
+    And STDERR should be empty
+
   Scenario: Handle themes with text domain different from slug
     Given a WP install
     And an empty cache
diff --git a/src/Core_Language_Command.php b/src/Core_Language_Command.php
index a2f5ac8c..16347599 100644
--- a/src/Core_Language_Command.php
+++ b/src/Core_Language_Command.php
@@ -389,6 +389,18 @@ public function uninstall( $args ) {
 	 * [--dry-run]
 	 * : Preview which translations would be updated.
 	 *
+	 * [--format=<format>]
+	 * : Render output in a particular format. When not specified, updates show
+	 *   progress messages and success/warning/error messages. When specified,
+	 *   the output format changes based on the selected format.
+	 * ---
+	 * options:
+	 *   - table
+	 *   - csv
+	 *   - json
+	 *   - summary
+	 * ---
+	 *
 	 * ## EXAMPLES
 	 *
 	 *     # Update installed core languages packs.
@@ -401,7 +413,7 @@ public function uninstall( $args ) {
 	 * @subcommand update
 	 *
 	 * @param string[] $args Positional arguments.
-	 * @param array{'dry-run'?: bool} $assoc_args Associative arguments.
+	 * @param array{'dry-run'?: bool, format?: string} $assoc_args Associative arguments.
 	 */
 	public function update( $args, $assoc_args ) { // phpcs:ignore Generic.CodeAnalysis.UselessOverridingMethod.Found -- Overruling the documentation, so not useless ;-).
 		parent::update( $args, $assoc_args );
diff --git a/src/Plugin_Language_Command.php b/src/Plugin_Language_Command.php
index a9bc5039..e6f10d3e 100644
--- a/src/Plugin_Language_Command.php
+++ b/src/Plugin_Language_Command.php
@@ -591,6 +591,18 @@ public function uninstall( $args, $assoc_args ) {
 	 * [--dry-run]
 	 * : Preview which translations would be updated.
 	 *
+	 * [--format=<format>]
+	 * : Render output in a particular format. When not specified, updates show
+	 *   progress messages and success/warning/error messages. When specified,
+	 *   the output format changes based on the selected format.
+	 * ---
+	 * options:
+	 *   - table
+	 *   - csv
+	 *   - json
+	 *   - summary
+	 * ---
+	 *
 	 * ## EXAMPLES
 	 *
 	 *     # Update all installed language packs for all plugins.
@@ -603,7 +615,7 @@ public function uninstall( $args, $assoc_args ) {
 	 * @subcommand update
 	 *
 	 * @param string[] $args Positional arguments.
-	 * @param array{'dry-run'?: bool, all?: bool} $assoc_args Associative arguments.
+	 * @param array{'dry-run'?: bool, all?: bool, format?: string} $assoc_args Associative arguments.
 	 */
 	public function update( $args, $assoc_args ) {
 		$all = \WP_CLI\Utils\get_flag_value( $assoc_args, 'all', false );
diff --git a/src/Theme_Language_Command.php b/src/Theme_Language_Command.php
index fd0548ac..7e5bce13 100644
--- a/src/Theme_Language_Command.php
+++ b/src/Theme_Language_Command.php
@@ -610,6 +610,18 @@ public function uninstall( $args, $assoc_args ) {
 	 * [--dry-run]
 	 * : Preview which translations would be updated.
 	 *
+	 * [--format=<format>]
+	 * : Render output in a particular format. When not specified, updates show
+	 *   progress messages and success/warning/error messages. When specified,
+	 *   the output format changes based on the selected format.
+	 * ---
+	 * options:
+	 *   - table
+	 *   - csv
+	 *   - json
+	 *   - summary
+	 * ---
+	 *
 	 * ## EXAMPLES
 	 *
 	 *     # Update all installed language packs for all themes.
@@ -622,7 +634,7 @@ public function uninstall( $args, $assoc_args ) {
 	 * @subcommand update
 	 *
 	 *  @param string[] $args Positional arguments.
-	 * @param array{'dry-run'?: bool, all?: bool} $assoc_args Associative arguments.
+	 * @param array{'dry-run'?: bool, all?: bool, format?: string} $assoc_args Associative arguments.
 	 */
 	public function update( $args, $assoc_args ) {
 		$all = \WP_CLI\Utils\get_flag_value( $assoc_args, 'all', false );
diff --git a/src/WP_CLI/CommandWithTranslation.php b/src/WP_CLI/CommandWithTranslation.php
index 02213f18..dc2d1da3 100644
--- a/src/WP_CLI/CommandWithTranslation.php
+++ b/src/WP_CLI/CommandWithTranslation.php
@@ -35,13 +35,20 @@ protected function sort_translations_callback( $a, $b ) {
 	 * Updates installed languages for the current object type.
 	 *
 	 * @param string[] $args Positional arguments.
-	 * @param array{'dry-run'?: bool, all?: bool} $assoc_args Associative arguments.
+	 * @param array{'dry-run'?: bool, all?: bool, format?: string} $assoc_args Associative arguments.
 	 */
 	public function update( $args, $assoc_args ) {
 		$updates = $this->get_translation_updates();
+		$format  = Utils\get_flag_value( $assoc_args, 'format' );
 
 		if ( empty( $updates ) ) {
-			WP_CLI::success( 'Translations are up to date.' );
+			if ( $format && in_array( $format, array( 'json', 'csv' ), true ) ) {
+				Utils\format_items( $format, array(), array() );
+			}
+
+			if ( ! $format || in_array( $format, array( 'table', 'summary' ), true ) ) {
+				WP_CLI::success( 'Translations are up to date.' );
+			}
 
 			return;
 		}
@@ -50,9 +57,17 @@ public function update( $args, $assoc_args ) {
 			$args = array( null ); // Used for core.
 		}
 
+		if ( $format && in_array( $format, array( 'json', 'csv' ), true ) ) {
+			$logger = new \WP_CLI\Loggers\Quiet();
+			WP_CLI::set_logger( $logger );
+		}
+
 		$upgrader      = 'WP_CLI\\LanguagePackUpgrader';
 		$results       = array();
+		$results_data  = array();
 		$num_to_update = 0;
+		$obj_type      = rtrim( $this->obj_type, 's' );
+		$slug_key      = 'core' === $obj_type ? 'version' : 'slug';
 
 		foreach ( $args as $slug ) {
 			// Gets a list of all languages.
@@ -105,7 +120,6 @@ public function update( $args, $assoc_args ) {
 				$updates_per_type[ $update->type ][] = $update;
 			}
 
-			$obj_type          = rtrim( $this->obj_type, 's' );
 			$available_updates = isset( $updates_per_type[ $obj_type ] ) ? $updates_per_type[ $obj_type ] : null;
 
 			if ( ! is_array( $available_updates ) ) {
@@ -117,7 +131,7 @@ public function update( $args, $assoc_args ) {
 			if ( ! Utils\get_flag_value( $assoc_args, 'dry-run' ) ) {
 				// Update translations.
 				foreach ( $available_updates as $update ) {
-					WP_CLI::line( "Updating '{$update->Language}' translation for {$update->Name} {$update->Version}..." );
+					WP_CLI::log( "Updating '{$update->Language}' translation for {$update->Name} {$update->Version}..." );
 
 					/**
 					 * @var \WP_CLI\LanguagePackUpgrader $upgrader_instance
@@ -129,6 +143,16 @@ public function update( $args, $assoc_args ) {
 					$result = $upgrader_instance->upgrade( $update );
 
 					$results[] = $result;
+
+					// Capture data for formatted output (skip for summary format).
+					if ( $format && 'summary' !== $format ) {
+						$slug_value     = 'version' === $slug_key ? $update->Version : $update->slug;
+						$results_data[] = array(
+							$slug_key  => $slug_value,
+							'language' => $update->language,
+							'status'   => $result ? 'updated' : 'failed',
+						);
+					}
 				}
 			}
 		}
@@ -137,29 +161,43 @@ public function update( $args, $assoc_args ) {
 		if ( Utils\get_flag_value( $assoc_args, 'dry-run' ) ) {
 			$update_count = count( $updates );
 
-			WP_CLI::line(
-				sprintf(
-					'Found %d translation %s that would be processed:',
-					$update_count,
-					WP_CLI\Utils\pluralize( 'update', $update_count )
-				)
-			);
-
-			Utils\format_items( 'table', $updates, array( 'Type', 'Name', 'Version', 'Language' ) );
+			if ( $format && in_array( $format, array( 'json', 'csv' ), true ) ) {
+				// For json/csv formats, just output the formatted data without the message
+				Utils\format_items( $format, $updates, array( 'Type', 'Name', 'Version', 'Language' ) );
+			} elseif ( ! $format || 'table' === $format ) {
+				// For table or no format, show the message and table
+				WP_CLI::line(
+					sprintf(
+						'Found %d translation %s that would be processed:',
+						$update_count,
+						WP_CLI\Utils\pluralize( 'update', $update_count )
+					)
+				);
+
+				Utils\format_items( 'table', $updates, array( 'Type', 'Name', 'Version', 'Language' ) );
+			}
+			// For 'summary' format, do nothing (no output for dry-run mode)
 
 			return;
 		}
 
 		$num_updated = count( array_filter( $results ) );
 
-		$line = sprintf( "Updated $num_updated/$num_to_update %s.", WP_CLI\Utils\pluralize( 'translation', $num_updated ) );
+		// Format output if --format is specified.
+		if ( $format && 'summary' !== $format ) {
+			Utils\format_items( $format, $results_data, array( $slug_key, 'language', 'status' ) );
+		}
+
+		if ( ! $format || in_array( $format, array( 'table', 'summary' ), true ) ) {
+			$line = sprintf( "Updated $num_updated/$num_to_update %s.", WP_CLI\Utils\pluralize( 'translation', $num_updated ) );
 
-		if ( $num_to_update === $num_updated ) {
-			WP_CLI::success( $line );
-		} elseif ( $num_updated > 0 ) {
-			WP_CLI::warning( $line );
-		} else {
-			WP_CLI::error( $line );
+			if ( $num_to_update === $num_updated ) {
+				WP_CLI::success( $line );
+			} elseif ( $num_updated > 0 ) {
+				WP_CLI::warning( $line );
+			} else {
+				WP_CLI::error( $line );
+			}
 		}
 	}