diff --git a/packages/integrations/vercel/src/serverless/adapter.ts b/packages/integrations/vercel/src/serverless/adapter.ts
index 8cddc0be10..5dbf24f4a6 100644
--- a/packages/integrations/vercel/src/serverless/adapter.ts
+++ b/packages/integrations/vercel/src/serverless/adapter.ts
@@ -134,7 +134,10 @@ export interface VercelServerlessConfig {
 	/** Whether to create the Vercel Edge middleware from an Astro middleware in your code base. */
 	edgeMiddleware?: boolean;
 
-	/** Whether to split builds into a separate function for each route. */
+	/**
+	 * Whether to split builds into a separate function for each route.
+	 * @deprecated `functionPerRoute` is deprecated and will be removed in the next major release of the adapter.
+	 */
 	functionPerRoute?: boolean;
 
 	/** The maximum duration (in seconds) that Serverless Functions can run before timing out. See the [Vercel documentation](https://vercel.com/docs/functions/serverless-functions/runtimes#maxduration) for the default and maximum limit for your account plan. */
@@ -286,6 +289,11 @@ export default function vercelServerless({
 							`\tMake sure to check your plan carefully to avoid incurring additional costs.\n` +
 							`\tYou can set functionPerRoute: false to prevent surpassing the limit.\n`,
 					);
+
+					logger.warn(
+						`\n` +
+							`\t\`functionPerRoute\` is deprecated and will be removed in a future version of the adapter.\n`
+					);
 				}
 
 				setAdapter(