diff --git a/common/envs/constants.ts b/common/envs/constants.ts
index c03c44bc..0a779b90 100644
--- a/common/envs/constants.ts
+++ b/common/envs/constants.ts
@@ -34,5 +34,9 @@ export const IS_PRIVATE_MANIFOLD = ENV_CONFIG.visibility === 'PRIVATE'
 export const CORS_ORIGIN_MANIFOLD = new RegExp(
   '^https?://(?:[a-zA-Z0-9\\-]+\\.)*' + escapeRegExp(ENV_CONFIG.domain) + '$'
 )
+// Vercel deployments, used for testing.
+export const CORS_ORIGIN_VERCEL = new RegExp(
+  '^https?://(?:[a-zA-Z0-9\\-]+\\.)*' + escapeRegExp('mantic.vercel.app') + '$'
+)
 // Any localhost server on any port
 export const CORS_ORIGIN_LOCALHOST = /^http:\/\/localhost:\d+$/
diff --git a/functions/src/api.ts b/functions/src/api.ts
index 290ea3d8..6ebffc24 100644
--- a/functions/src/api.ts
+++ b/functions/src/api.ts
@@ -8,6 +8,7 @@ import { PrivateUser } from '../../common/user'
 import {
   CORS_ORIGIN_MANIFOLD,
   CORS_ORIGIN_LOCALHOST,
+  CORS_ORIGIN_VERCEL,
 } from '../../common/envs/constants'
 
 type Output = Record<string, unknown>
@@ -118,7 +119,7 @@ const DEFAULT_OPTS = {
   concurrency: 100,
   memory: '2GiB',
   cpu: 1,
-  cors: [CORS_ORIGIN_MANIFOLD, CORS_ORIGIN_LOCALHOST],
+  cors: [CORS_ORIGIN_MANIFOLD, CORS_ORIGIN_VERCEL, CORS_ORIGIN_LOCALHOST],
 }
 
 export const newEndpoint = (endpointOpts: EndpointOptions, fn: Handler) => {