What causes "GitHub Codespaces Port Forwarding Not Working"?

App did not print a localhost URL to the console Typing localhost on your machine while using the browser editor does not reach the codespace Codespace stopped after inactivity, which stopped your app An organization policy restricts port visibility A hardcoded forwarded URL broke because GitHub can change the forwarding domain

How do I fix "GitHub Codespaces Port Forwarding Not Working"?

1. Forward and open the port: Add the port manually in the Ports tab Open it from the notification in the bottom-right of VS Code or by clicking the URL in the Terminal 2. After a restart: Start the application again once the codespace restarts 3. Visibility and URLs: If Public or Organization is missing, ask an admin about the port visibility policy Use environment variables instead of hardcoded forwarded URLs in tests

GitHub Codespaces Port Forwarding Not Working

Workaround available Browser, VS Code Updated November 14, 2026How we research

Quick answer

Codespaces forwards a port only when the app prints a localhost URL. Forward it manually, open it from the VS Code notification or Ports tab (not localhost in your own browser), and restart the app after the codespace wakes.

Most likely fix: Forward and open the port

How to fix it

Try these in order — the most common fix is first.

1. Forward and open the port
1. Add the port manually in the Ports tab
2. Open it from the notification in the bottom-right of VS Code or by clicking the URL in the Terminal
Did this fix it?
2. After a restart
1. Start the application again once the codespace restarts
Did this fix it?
3. Visibility and URLs
1. If Public or Organization is missing, ask an admin about the port visibility policy
2. Use environment variables instead of hardcoded forwarded URLs in tests
Did this fix it?

Symptoms

Forwarded port will not open, is not forwarded automatically, stops after a restart, or the public/organization visibility option is missing.

Why it happens

App did not print a localhost URL to the console
Typing localhost on your machine while using the browser editor does not reach the codespace
Codespace stopped after inactivity, which stopped your app
An organization policy restricts port visibility
A hardcoded forwarded URL broke because GitHub can change the forwarding domain

This guide also covers

codespaces port forwarding not working
codespace port not opening
codespaces localhost not working

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