OpenRouter returned a billing error:

Error: Insufficient credits. Please add funds.

Or your payment failed. Here is how to fix it.

Fix 1: Check credit balance

# Check balance
curl https://openrouter.ai/api/v1/auth/key \
  -H "Authorization: Bearer $OPENROUTER_API_KEY"

Fix 2: Add credits

1. Go to openrouter.ai/credits
2. Click “Add Credits”
3. Enter amount ($5-20 recommended)
4. Complete payment

Fix 3: Fix payment method

If payment fails:

1. Check card details are correct
2. Ensure card is not expired
3. Check if card is blocked for international payments
4. Try a different card

Fix 4: Use free tier

Some models are free:

# Free models available
model = "meta-llama/llama-3-8b:free"
model = "mistralai/mistral-7b:free"

# Free tier limits apply

Fix 5: Check usage

See where credits went:

# Check usage history
curl https://openrouter.ai/api/v1/activity \
  -H "Authorization: Bearer $OPENROUTER_API_KEY"

Fix 6: Set spending limits

Prevent surprise charges:

// In your code
{
  "model": "anthropic/claude-sonnet-5",
  "max_tokens": 1000,
  "metadata": {
    "user_id": "my-app",
    "limit": "10.00"
  }
}

Still not working?

1. Contact support — support@openrouter.ai
2. Check email — Payment confirmation may have issues
3. Try PayPal — Alternative payment method
4. Use free models — While resolving billing

FAQ

How do I add credits to OpenRouter?

Go to openrouter.ai/credits, click “Add Credits”, enter an amount ($5-20 recommended), and complete payment. Credits are used as you make API calls.

Why did my payment fail?

Common causes: card declined, expired card, international payment restrictions, or insufficient funds. Try a different card or PayPal. Contact support if issues persist.

Can I use OpenRouter without adding credits?

Yes. Some models are free (with :free suffix). The free tier has lower limits but works for testing and light use. See our Best Free AI APIs guide for details.

Related: OpenRouter Complete Guide · OpenRouter Rate Limit Fix · AI API Pricing Compared 2026 · Best Free AI APIs 2026