Upstash Redis Environment Variables Not Found (Vercel KV, Fly.io)

How to fix it

// try these in order, the most common fix is first

1. FIX 1Set the REST variables

   Copy steps
   1. 01Upstash Console > database > Connect > REST tab
   2. 02Add UPSTASH_REDIS_REST_URL and UPSTASH_REDIS_REST_TOKEN to your platform's environment settings
   3. 03Redeploy
   Did this fix it? Yes No

2. FIX 2Fix projects migrated from Vercel KV

   Copy steps
   1. 01Replace @vercel/kv with @upstash/redis
   2. 02Keep KV_REST_API_URL/KV_REST_API_TOKEN (fromEnv reads them) or switch to the UPSTASH_ names
   3. 03If the store is missing in Vercel Storage, create a database in the Upstash Console and add its env vars to the project
   Did this fix it? Yes No

3. FIX 3On Fly.io, use TCP or a direct database

   Copy steps
   1. 01The Fly.io extension only offers the Redis protocol: use ioredis/redis with the rediss:// URL
   2. 02If you need REST (edge functions), create the database directly at console.upstash.com instead
   Did this fix it? Yes No

4. FIX 4Pass credentials explicitly

   1. 01new Redis({ url: process.env.X, token: process.env.Y }) to rule out naming issues
   Did this fix it? Yes No

Symptoms

The SDK warns it can't find UPSTASH_REDIS_REST_URL, requests go to 'undefined', the app broke after the Vercel KV to Upstash migration, or no REST URL exists for a Fly.io Upstash database.

Why it happens

• C-01Env vars set locally (.env) but not in the deployment
• C-02Vercel KV store migrated to Upstash and the project still expects old variable names
• C-03Fly.io Upstash Redis extension doesn't provide the REST API
• C-04Variables set for Production but the code runs in Preview

// this guide also covers

• upstash_redis_rest_url not found
• upstash redis fromenv error
• vercel kv upstash migration
• fly io upstash rest api

The same problem in other apps

All not loading, error messages & connection guides →

• Redis Cloud Connection Timeout (Redis Cloud)
• Pinecone 429 Too Many Requests Error (Pinecone)

Other Upstash errors

• Upstash ERR Max Requests Limit Exceeded
• Upstash ERR Max Request Size Exceeded
• Upstash Redis ECONNRESET Error
• Upstash WRONGPASS Invalid or Missing Auth Token
• Upstash ERR Max Concurrent Connections Exceeded
• Upstash Free Database Archived or Deleted
• Upstash Redis Slow or Timing Out
• QStash Signature Verification Failed (Invalid Signature)