Stripe MPP Guide: Accept USDC Micropayments in 2026

Stripe and Tempo announced the Machine Payments Protocol (MPP) on March 18, 2026. The protocol allows API sellers to present an HTTP 402 payment challenge to automated agents, accept Tempo USDC.e or Solana USDC micropayments, and have the resulting funds deposited into their existing Stripe balances.

Under MPP, a client requesting a paid API resource receives an HTTP 402 challenge from the seller’s server. The client authorizes payment and retries the request with a credential. The seller records a PaymentIntent with Stripe, the client receives the requested resource and a receipt, and the payment settles into the seller’s Stripe balance. Stripe’s documentation notes that refunds, reporting, Connect charge types and Dashboard workflows continue to operate on the same Stripe stack after settlement.

To implement MPP sellers must create a Stripe profile and pass the profile ID as networkId when creating the MPP endpoint. Stripe documents retrieving the profile ID through the Business Profiles API. Developers install the seller SDK and Stripe client with npm install mppx stripe, initialize mppx via stripe.create({ client, networkId, livemode }), and then call Mppx.create with the Stripe secret key and default methods. The quickstart derives a challenge-binding secret from the Stripe secret key to prevent forged challenges and calls mppx.charge({ amount: ‘0.50’ }) to emit a 402 and withReceipt(…) when a payment completes.

Stablecoin micropayments require a $0.01 USDC minimum. Shared Payment Tokens (SPTs), which act like card grants for agents, have a $0.50 minimum. The quickstart supports SPTs by default. To accept stablecoins for micropayments sellers must create a crypto deposit address and attach it under depositAddresses when initializing Stripe’s helper. Stripe documents address creation via POST /v1/crypto/deposit_addresses with network=tempo (preview Stripe-Version). Returned addresses should be stored as environment variables and deposit-address creation should be kept off the hot request path.

Availability is limited to U.S. sellers in all states except New York. Businesses outside the U.S. can request access by emailing machine-payments@stripe.com with their Stripe account ID; fee sponsorship for Tempo network fees and Directory listing are available by request and are listed as private preview items that require the same email. Solana deposit wiring is supported when matching deposit network parameters appear in a seller’s Stripe Dashboard and documentation.

Testing tools include npx mppx@latest validate to exercise local, sandbox and live endpoints. For SPT tests Stripe points to link-cli (npx @stripe/link-cli). For crypto tests developers should use the Tempo CLI, fund a wallet and perform requests against the paid path. Documentation warns that live deposit addresses move real funds and recommends validating in sandbox mode before switching to live keys.

Stripe frames MPP as a seller-side protocol for automated agents that can satisfy an HTTP 402 challenge. The company distinguishes MPP from Stripe’s x402 path on Base USDC and from Stripe Link human stablecoin checkout, which use different integration lanes and documentation. Sellers are advised to claim their Stripe profile ID, enable Stablecoins and Crypto where eligible, install mppx, create a Tempo deposit address, attach it under depositAddresses, and run validation before using live keys.