How to Fix Claude API 402 Payment Required Error

The Anthropic API returns an invalid_request_error with a 402 status code ("payment_required") when your account has run out of funds or has an outstanding invoice. Unlike the Claude consumer interface, the developer API relies on a separate prepaid credit system or monthly billing pipeline. If your credit balance drops to zero, Anthropic immediately halts all API key operations.

This guide walks you through diagnosing, funding, and resolving a 402 billing block on your Claude API integration.

Why the 402 Error Occurs When you send a request to `api.anthropic.com`, the server validates your organization's financial status before processing your prompt tokens. The system blocks the request if: * **Zero Credit Balance:** Your prepaid wallet is empty. * **Expired Credits:** Promotional or trial credits have reached their expiration date. * **Hard Limit Reached:** You set a custom spending limit in the Console, and your usage met that limit, preventing further charges even if you have valid payment methods on file. * **Failed Invoicing:** For postpaid accounts, a monthly invoice payment failed to process.

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How to Fix a Claude API 402 Error

Follow these steps to restore service to your API keys.

1. Check Your Console Credit Balance Do not rely on your bank statement; verify your actual balance directly inside the developer dashboard. 1. Log in to the [Anthropic Console](https://console.anthropic.com/). 2. Navigate to the **Billing** tab in the left-hand navigation menu. 3. Look at your **Prepaid Credits** balance. 4. If the balance reads `$0.00`, your API calls will remain blocked until funded.

2. Purchase Additional Credits If your balance is zero, you must manually fund the account to lift the block. 1. On the **Billing** page, click **Add Funds**. 2. Enter the amount of USD you wish to load onto your account (minimum purchase requirements may apply). 3. Enter your credit card details and confirm the payment. 4. **Important:** Wait 5 to 10 minutes. While many transactions clear instantly, API rate limits and billing state caches can take up to 15 minutes to sync across all edge nodes.

3. Check and Adjust Your Spend Limits Even with money in your account, custom monthly spend ceilings can trigger 402 errors or simulated rate-limit blocks. 1. In the **Billing** section, scroll down to **Spend Limits**. 2. Review your current **Monthly Hard Limit** and **Monthly Soft Limit**. 3. If your current monthly spend matches your Hard Limit, you must increase this ceiling to resume API access. 4. Save your updated limits and wait a few minutes for the changes to propagate.

4. Enable Auto-Recharge to Prevent Future Outages To prevent your production applications from crashing when credit balances dip, configure automatic funding. 1. Go to the **Billing** tab in the Console. 2. Click on **Auto-recharge** or **Payment Settings**. 3. Toggle Auto-recharge to **Enabled**. 4. Set your threshold rule: "When my balance falls below `$X`, charge my card `$Y`." 5. Ensure your credit card expiration date is up to date.

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When to Escalate If you have added funds, your console balance shows a positive USD amount, your spend limits are cleared, and you still receive a `402 Payment Required` error after 30 minutes, contact support.

Go to the Anthropic Console, click the Support or help icon in the bottom right corner, and open a ticket. Provide your Organization ID (found under Settings) and a screenshot of your Billing dashboard to expedite account reactivation.