diff --git a/includes/class-convertkit-setup.php b/includes/class-convertkit-setup.php
index 1730d0adc..6cb68da5b 100644
--- a/includes/class-convertkit-setup.php
+++ b/includes/class-convertkit-setup.php
@@ -151,11 +151,31 @@ public function update() {
 			$posts->schedule_cron_event();
 		}
 
+		// Actions that should run regardless of the version number
+		// whenever the Plugin is updated.
+		$this->remove_v3_api_secret_from_settings();
+
 		// Update the installed version number in the options table.
 		update_option( 'convertkit_version', CONVERTKIT_PLUGIN_VERSION );
 
 	}
 
+	/**
+	 * Remove v3 API Secret from settings.
+	 *
+	 * @since   3.2.4
+	 */
+	private function remove_v3_api_secret_from_settings() {
+
+		$settings = new ConvertKit_Settings();
+		$settings->save(
+			array(
+				'api_secret' => '',
+			)
+		);
+
+	}
+
 	/**
 	 * Adds form_id column and key to form entries database table.
 	 *
diff --git a/tests/EndToEnd/general/other/UpgradePathsCest.php b/tests/EndToEnd/general/other/UpgradePathsCest.php
index 94d4f1c39..65cabca4c 100644
--- a/tests/EndToEnd/general/other/UpgradePathsCest.php
+++ b/tests/EndToEnd/general/other/UpgradePathsCest.php
@@ -127,11 +127,9 @@ public function testGetAccessTokenByAPIKeyAndSecret(EndToEndTester $I)
 		$I->assertArrayHasKey('refresh_token', $settings);
 		$I->assertArrayHasKey('token_expires', $settings);
 
-		// Confirm the API Key and Secret are retained, in case we need them in the future.
+		// Confirm the API Key is retained, as it's needed for Legacy Forms.
 		$I->assertArrayHasKey('api_key', $settings);
-		$I->assertArrayHasKey('api_secret', $settings);
 		$I->assertEquals($settings['api_key'], $_ENV['CONVERTKIT_API_KEY']);
-		$I->assertEquals($settings['api_secret'], $_ENV['CONVERTKIT_API_SECRET']);
 
 		// Go to the Plugin's Settings Screen.
 		$I->loadKitSettingsGeneralScreen($I);
@@ -258,6 +256,39 @@ public function testUpdateFormEntriesTableAddsFormIDColumn(EndToEndTester $I)
 		$I->seeColumnInDatabase('wp_kit_form_entries', 'form_id');
 	}
 
+	/**
+	 * Tests that the v3 API Secret is removed from settings when upgrading to 3.2.4 or later.
+	 *
+	 * @since   3.2.4
+	 *
+	 * @param   EndToEndTester $I  Tester.
+	 */
+	public function testV3APISecretRemovedFromSettings(EndToEndTester $I)
+	{
+		// Setup Plugin with v3 API Key and Secret.
+		$I->setupKitPlugin(
+			$I,
+			[
+				'api_key'      => $_ENV['CONVERTKIT_API_KEY'],
+				'api_secret'   => $_ENV['CONVERTKIT_API_SECRET'],
+				'post_form'    => '',
+				'page_form'    => '',
+				'product_form' => '',
+			]
+		);
+
+		// Define an installation version older than 3.2.4.
+		$I->haveOptionInDatabase('convertkit_version', '3.2.0');
+
+		// Activate the Plugin.
+		$I->activateKitPlugin($I, false);
+
+		// Confirm the settings no longer have a value for the v3 API Secret.
+		$settings = $I->grabOptionFromDatabase('_wp_convertkit_settings');
+		$I->assertEquals($settings['api_key'], $_ENV['CONVERTKIT_API_KEY']);
+		$I->assertEquals($settings['api_secret'], '');
+	}
+
 	/**
 	 * Deactivate and reset Plugin(s) after each test, if the test passes.
 	 * We don't use _after, as this would provide a screenshot of the Plugin