diff --git a/apps/www/lib/go.ts b/apps/www/lib/go.ts
index dce09d01cdb..9a14bbc6188 100644
--- a/apps/www/lib/go.ts
+++ b/apps/www/lib/go.ts
@@ -3,7 +3,12 @@ import { goPageSchema, type GoPage } from '@/types/go'
 
 function isExpired(page: { expiresAt?: string }): boolean {
   if (!page.expiresAt) return false
-  return new Date(page.expiresAt) < new Date()
+  const [year, month, day] = page.expiresAt.split('-').map(Number)
+  if (![year, month, day].every(Number.isInteger)) {
+    throw new Error(`Invalid expiresAt value: "${page.expiresAt}"`)
+  }
+  const expiresAtEndOfDayUtc = Date.UTC(year, month - 1, day, 23, 59, 59, 999)
+  return Date.now() > expiresAtEndOfDayUtc
 }
 
 export function getAllGoPages(): GoPage[] {
diff --git a/packages/marketing/src/go/schemas.ts b/packages/marketing/src/go/schemas.ts
index 20eb7ab3c99..b1ab549f02d 100644
--- a/packages/marketing/src/go/schemas.ts
+++ b/packages/marketing/src/go/schemas.ts
@@ -333,7 +333,10 @@ const goPageBaseSchema = z.object({
   sections: z.array(goSectionSchema).optional(),
   publishedAt: z.string().optional(),
   /** ISO 8601 date (YYYY-MM-DD) after which the page should return a 404. */
-  expiresAt: z.string().optional(),
+  expiresAt: z
+    .string()
+    .regex(/^\d{4}-\d{2}-\d{2}$/, 'expiresAt must be YYYY-MM-DD')
+    .optional(),
 })
 
 export const leadGenPageSchema = goPageBaseSchema.extend({