Fixing “Property 'user' does not exist on type 'Request'” in Express + TypeScript

📰 Dev.to · Chukwuemeka Ngumoha

Learn to fix the 'Property user does not exist on type Request' error in Express + TypeScript by using declaration merging

intermediate Published 25 Apr 2026
Action Steps
  1. Install the @types/express package to get the base type definitions for Express
  2. Extend the Request type using declaration merging to add a custom 'user' property
  3. Use the augmented Request type in your Express routes to access the 'user' property
  4. Configure your TypeScript config to include the declaration merging file
  5. Test your Express application to ensure the error is resolved
Who Needs to Know This

Backend developers using Express and TypeScript will benefit from this tutorial as it helps resolve a common error when trying to access custom properties on the Request object

Key Insight

💡 Use declaration merging to extend the type definitions of built-in modules in Express and other external packages

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🚀 Fix the 'Property user does not exist on type Request' error in Express + TypeScript using declaration merging! 💡

Key Takeaways

Learn to fix the 'Property user does not exist on type Request' error in Express + TypeScript by using declaration merging

Full Article

A simple tutorial aimed at helping developers understand how to extend the definitions of built in modules in express and other external packages using the mechanism of declaration merging in Node.js with TypeScript.
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