Stripe Bridge - Accept Crypto Payments, Get Paid in USD

The x402 protocol makes it trivially easy for developers to monetize APIs with crypto payments. But what about API providers who want the simplicity of Stripe and traditional banking? What about businesses that need USD in their bank account, not USDC in a wallet?

Stripe Bridge solves this. It connects the x402 crypto payment rail to Stripe's fiat settlement system, giving API providers the best of both worlds: a global, permissionless buyer base paying in crypto, with automatic USD payouts to a standard bank account.

The Problem

x402 is powerful, but it assumes both sides of the transaction are comfortable with crypto. The buyer needs a wallet with USDC. The seller receives USDC to their wallet. For many API providers - especially traditional SaaS companies, indie developers, or businesses in regulated industries - receiving crypto directly is not an option. They need fiat. They need invoices. They need Stripe.

At the same time, forcing buyers to use credit cards defeats the purpose of x402. The whole point is permissionless, instant, global payments with no accounts, no KYC for small amounts, and no chargebacks. AI agents cannot fill out credit card forms. Crypto wallets can.

Stripe Bridge keeps the buyer experience pure x402 while giving the seller a pure Stripe experience.

How It Works

The flow is straightforward:

For the API Provider (Seller)

1. Connect Stripe - Link your Stripe account through RelAI's dashboard. This uses Stripe Connect, the same system that powers marketplaces like Shopify and Uber.
2. Create an API - Use the standard RelAI API creation flow. In the payment settings, select "Stripe Bridge" as the settlement method.
3. Get paid - Every time someone calls your API and pays with USDC, RelAI automatically converts the payment and transfers USD to your Stripe account. You see the settlement in your Stripe dashboard just like any other payment.

For the Buyer

Nothing changes. The buyer sees a standard x402-protected API. They connect their Solana or EVM wallet, approve the USDC payment, and get the API response. The entire Stripe settlement happens invisibly on the backend after the transaction confirms on-chain.

Under the Hood

Here is what happens in the milliseconds between the buyer clicking "Pay" and the seller seeing USD in Stripe:

1. Buyer signs USDC transfer to RelAI's payment wallet on Solana (or an EVM chain)
2. RelAI's facilitator co-signs and submits the transaction on-chain, sponsoring gas fees
3. Transaction confirms on the blockchain - the USDC is now in RelAI's custody
4. RelAI creates a Stripe Transfer from its platform account to the provider's Connected Account
5. Provider receives fiat in their Stripe balance, ready for payout to their bank

Why This Matters

For API Providers

• No crypto infrastructure needed - No wallets, no private keys, no token accounting. Just Stripe.
• Familiar settlement - See payments in your Stripe dashboard. Use Stripe's reporting, invoicing, and tax tools.
• Bank payouts - Stripe handles the final mile, sending money to your bank account on your schedule.
• Global reach - Accept payments from anyone with a crypto wallet, anywhere in the world. No payment processor restrictions, no declined cards, no chargebacks.

For Buyers

• Same x402 experience - Connect wallet, approve payment, get data. No change in workflow.
• Gas-free payments - RelAI sponsors transaction fees through its facilitator, so buyers only pay the API price.
• AI agent compatible - Autonomous agents can pay for Stripe Bridge APIs exactly like any other x402 API. The settlement method is invisible to the caller.

For the Ecosystem

Stripe Bridge lowers the barrier to entry for x402 adoption. API providers who would never touch crypto can now participate in the x402 economy. This means more APIs in the marketplace, which means more utility for crypto-native buyers and AI agents.

It also creates a clean regulatory story. The provider deals exclusively with Stripe and fiat. The crypto side is handled by RelAI as an intermediary. Both sides operate in their comfort zone.

Setting It Up

Getting started takes about five minutes:

1. Go to Dashboard > Stripe in the RelAI console
2. Click Connect Stripe and complete the Stripe Connect onboarding
3. Create a new API at Dashboard > New API
4. In the "Payment Settlement" section, select Stripe Bridge
5. Publish your API

What About Fees?

Stripe Bridge has a transparent fee structure:

• x402 payment - Standard USDC transfer on-chain (gas sponsored by RelAI)
• Bridge fee - A percentage is retained by RelAI for the crypto-to-fiat conversion and Stripe transfer
• Stripe fees - Standard Stripe Connect fees apply for payouts to your bank

What's Next

Stripe Bridge is live today on RelAI for Solana USDC payments, with EVM chain support following shortly. We are also working on:

• Real-time settlement dashboard - Track every bridge settlement with on-chain tx hash linked to Stripe transfer ID
• Multi-currency support - Automatic conversion to your Stripe account's local currency (USD, EUR, GBP, PLN, and more)
• Webhook notifications - Get notified on every settlement with full transaction details
• Bulk settlement - Option to batch multiple small payments into periodic Stripe transfers to reduce fees