A blockchain payment API lets your product accept or send stablecoin and crypto payments with a few API calls, while the provider watches the chain, confirms each payment, and settles to you in crypto or fiat. If you already use Stripe, its stablecoin payments are the simplest route: customers pay in USDC, you're settled in USD, and refunds and subscriptions use the same API. Coinbase Business suits teams that want to keep USDC; BitPay and Triple-A suit merchants that want many coins in and local currency out; and x402 is the option for charging AI agents and apps per request.
This comparison covers nine APIs for developers and product teams adding checkout, invoices, subscriptions, or payouts: what each accepts and sends, where it settles, and what it charges where prices are public. If you need one integration to move money between bank accounts and stablecoins across many countries, see our comparison of stablecoin orchestration platforms instead.
Blockchain Payment APIs Compared
Coverage and fees below are from each provider's website and developer docs as of November 2026.
| API | Accept / Send | Chains and Tokens | Settles In | Published Fees | Who Can Use It |
|---|---|---|---|---|---|
| APIStripe | Accept / SendAccept; send in preview | Chains and TokensUSDC on  Base,  Ethereum,  Polygon,  Solana, Tempo; USDP and USDG in the US | Settles InUSD in your Stripe balance | Published FeesNot stated in docs | Who Can Use ItUS businesses outside New York; EU, Hong Kong, Mexico, and Switzerland in preview |
| APICoinbase Business | Accept / SendBoth | Chains and TokensUSDC on Ethereum, Base, Polygon,  Optimism,  Arbitrum, Solana; USDT on Ethereum | Settles InUSDC; USD or USDC for enterprise acceptance | Published FeesShown in your account | Who Can Use ItCoinbase Business account holders |
| APICircle | Accept / SendBoth | Chains and TokensUSDC and EURC on 25+ chains | Settles InUSDC or EURC | Published FeesCCTP standard transfers free; others not public | Who Can Use ItAny developer (Wallets, Gateway, CCTP) |
| APIPayPal | Accept / SendAccept | Chains and TokensAbout 100 cryptocurrencies, incl. BTC, ETH, USDC, PYUSD | Settles InLocal currency in your PayPal balance | Published FeesNot stated since Aug 2026 (0.99% launch rate ended 31 July 2026) | Who Can Use ItUS merchants only |
| APIBitPay | Accept / SendBoth | Chains and Tokens100+ cryptocurrencies, incl. BTC, ETH, USDC, USDT | Settles InCrypto or 7 fiat currencies | Published Fees2% + 25¢, falling to 1% + 25¢ with volume | Who Can Use ItUS (NYDFS and state licences) and EU (MiCA) |
| APINOWPayments | Accept / SendBoth | Chains and Tokens300+ assets | Settles InCrypto; EUR off-ramp | Published FeesFrom 1%; no service fee on mass payouts | Who Can Use ItNo licence stated |
| APITriple-A | Accept / SendBoth | Chains and TokensUSDC, USDT, PYUSD, BTC, ETH, and 20+ more on Ethereum,  TRON,  BNB Chain, Polygon, Solana | Settles InLocal currency next day, or stablecoins | Published FeesNot published | Who Can Use ItSingapore, EU (MiCA), parts of the US, Canada |
| APICryptoProcessing by CoinsPaid | Accept / SendBoth | Chains and Tokens20+ cryptocurrencies; USDC, USDG, EURC, EURS | Settles In40+ fiat currencies, or crypto | Published Fees1.5% or less, quoted per merchant | Who Can Use ItUS and Canadian MSB registrations |
| APICrossmint | Accept / SendBoth | Chains and TokensStablecoins on 50+ chains (its count) | Settles InStablecoins; off-ramp to a bank | Published FeesWallets $0.01 each after 5,000; transfers quoted | Who Can Use ItEU (MiCA), US and Canada MSB |
What a Blockchain Payment API Does
A blockchain payment API sits between your product and the chains your customers pay on, and turns an onchain transfer into what a card API gives you: a payment with an amount, a status, and an event when the status changes. A typical checkout runs like this:
- Your server creates a payment with the amount, the currency you price in, and your order ID. The provider returns a hosted checkout page, or the deposit address, token, chain, amount due, and expiry time to show in your own interface.
- The customer pays from a wallet or exchange. The provider usually fixes the exchange rate for a short window, so a price set in USD converts to a set number of tokens.
- The provider watches the chain. It matches the incoming transfer to your payment, checks the amount, token, and chain, and waits for enough confirmations.
- A webhook tells your server whether the payment is confirmed, underpaid, overpaid, or expired, and you fulfil the order.
- The provider settles. Funds stay in your balance as crypto or stablecoins, or pay out to your bank in fiat, depending on the provider and your settings.
Sending runs the other way. You fund a balance, call a payout endpoint with an address, chain, and amount, and the provider broadcasts the transfer, returns its transaction hash, and sends a webhook once it confirms.
Webhooks
Webhooks are the provider's calls to your server when a payment changes status, and most integrations depend on them. Check that each one is signed by the provider, and make your handler safe to run twice, because providers retry when your server doesn't answer.
Confirmations and Finality
A transfer is visible onchain before it is final. Providers wait for a number of blocks before marking a payment as paid, and the wait depends on the chain: a 
Bitcoin block takes about ten minutes, an Ethereum transaction takes about 13 minutes to finalise, and stablecoin transfers on faster chains confirm in seconds. Ask each provider how long it waits per chain, because that sets how quickly you can ship an order.
Refunds
Onchain payments have no chargeback. A customer can't reverse a transfer, so a refund is a new payment from you to the customer's wallet. Decide in advance whether you refund the token amount or its value in your pricing currency, since the two drift apart on anything other than a stablecoin. Some APIs run refunds for you; others leave them to your payouts.
Blockchain Payment API Profiles
Stripe
Stripe's documentation says that with stablecoin payments, "completed payments settle in your Stripe balance in your local currency." Customers pay from a crypto wallet on a Stripe-hosted page, in USDC on Base, Ethereum, Polygon, Solana, or Tempo, or in USDP and USDG for US businesses, and the payment works like any other in Checkout, Elements, Payment Links, Invoicing, and Connect. Refunds go back in stablecoins to the customer's original wallet, there are no disputes, and a single payment can be up to $10,000. To send, a Stripe financial account can hold USDC or OUSD and pay out to wallets or banks (public preview in the US).
Stripe's docs don't state a rate for stablecoin payments. Acceptance is open to US businesses outside New York after a review, and in private preview in the EU, Hong Kong, Mexico, and Switzerland. It suits businesses already on Stripe that want fiat in the bank.
Coinbase Business
Coinbase now steers merchants from Coinbase Commerce to Coinbase Business, and its docs recommend that Commerce users migrate from the old Charge API to the Checkouts API, which requires a Coinbase Business account. Hosted checkouts accept USDC on Ethereum, Base, Polygon, Optimism, Arbitrum, and Solana, plus USDT on Ethereum. They settle in USDC to your Coinbase Business account, with refunds, payment webhooks, and a sandbox on the Base Sepolia testnet. For PSPs, marketplaces, and large platforms, Coinbase Developer Platform's Payment Acceptance adds authorisation and capture, recurring payments, and settlement in USD or USDC, after about a month of enhanced due diligence.
Fees aren't published. Coinbase also created x402 and runs a facilitator for it (see below). It suits teams that want to keep USDC.
Circle
Circle, the issuer of USDC and EURC, doesn't sell a merchant checkout. It sells the building blocks under many of the APIs here: Circle Wallets for embedded, developer-controlled, or user-controlled wallets; Gateway, one USDC balance usable across chains; and CCTP, which moves native USDC between chains. Its x402 facilitator settles USDC on 
Arc, Base, and Polygon PoS.
CCTP is free for standard transfers, and Gateway needs no sign-up. For fiat conversion and cross-border settlement, institutions use Circle Mint and Circle Payments Network, covered in our comparison of stablecoin orchestration platforms. Circle suits developers building directly on USDC.
PayPal
PayPal's Pay with Crypto, launched in July 2025, lets US merchants accept about 100 cryptocurrencies, including Bitcoin, Ethereum, and PayPal USD (PYUSD), and settles in local currency in your PayPal balance. It runs through PayPal's Orders API, and refunds are paid in PYUSD, so you don't need to hold crypto to issue them. Recurring payments, billing agreements, authorisation and capture, and chargebacks are not supported.
PayPal launched it at 0.99% per transaction, a rate it said would apply until 31 July 2026, and its developer page now mentions only "competitive transaction fees," so confirm the current rate. It requires a verified US PayPal Business account. It suits US merchants already selling through PayPal.
BitPay
BitPay has processed crypto payments since 2011. It accepts 100+ cryptocurrencies, including USDC and USDT, and settles in crypto or in seven fiat currencies: AUD, CAD, EUR, GBP, MXN, NZD, and USD. The API covers invoices, refunds, payouts, and settlements, with webhook notifications and e-commerce plugins.
BitPay publishes its pricing: 2% + 25¢ per transaction below $500,000 a month, 1.5% + 25¢ up to $1 million, and 1% + 25¢ above that, with higher fees for high-risk industries. It holds US state money transmitter licences and a New York virtual currency licence, and its Dutch entity was authorised under MiCA in July 2026. It suits merchants that want many coins in and local currency out.
NOWPayments
NOWPayments accepts 300+ assets, by its count, and offers invoices, recurring payments, a custody API, mass payouts, and a free sandbox. Settlement is in crypto, with an EUR off-ramp through a partner. Since June 2026 new accounts are custodial by default, with an option to switch to non-custodial.
Fees start at 1%, with an extra charge when the customer pays in a different coin from the one you receive, and mass payouts carry only network fees. The site names no licence, and some of its pages say the service is unavailable in certain locations for regulatory reasons. It suits crypto-native businesses that want breadth of coins more than fiat settlement.
Triple-A
Triple-A accepts USDC, USDT, PYUSD, Bitcoin, Ethereum, and 20+ other assets on Ethereum, TRON, BNB Chain, Polygon, and Solana, and settles in your local currency the next day, so you "never need to hold, manage, or custody digital assets." It also sends stablecoin payouts and local-currency payouts in 30+ currencies.
Triple-A doesn't publish a price list; its WooCommerce plugin advertises a 1% settlement fee. It is a Major Payment Institution licensed by the Monetary Authority of Singapore, holds a French payment institution licence and a MiCA authorisation from France's AMF, and is registered in Canada. In the US it holds money transmitter licences in some states, with California, New York, and Texas still in progress. It suits merchants that want many coins in and local currency out.
CryptoProcessing by CoinsPaid
In July 2026 CoinsPaid split into independent companies, and its merchant gateway now runs as CryptoProcessing. It accepts 20+ cryptocurrencies, including stablecoins USDC (on Ethereum, Solana, Base, and Arbitrum), USDG, EURC, and EURS, and settles in crypto or in 40+ fiat currencies. It also offers mass payouts and e-commerce plugins.
It charges "1.5% or less per transaction," with volume discounts and no setup or monthly fees. Its legal entities hold US and Canadian money services business registrations, and its Lithuanian entity has suspended crypto-asset services, so check which entity would contract with you. It serves industries including iGaming and forex.
Crossmint
Crossmint calls itself "the platform for programmable money": wallets, stablecoin pay-ins and payouts, swaps, on- and off-ramps, checkout, and payments for AI agents, including x402. It claims support for 50+ chains, settles in stablecoins with an off-ramp to a bank, signs its webhooks, and has a staging environment with test tokens.
Pricing is partly public: wallets are free up to 5,000 monthly active wallets, then $0.01 each, and agent checkout costs $0.05 after the first 1,000, while stablecoin transfers carry a per-transaction fee quoted on request. Its Spanish entity holds a MiCA authorisation from the CNMV, issued in January 2026. It suits apps that need wallets and agent payments more than merchants that want fiat in the bank.
x402: Stablecoin Payments for APIs and AI Agents
x402 is an open protocol that turns the web's "402 Payment Required" status code into a payment step, so software, including AI agents, can pay for an API call or a page in stablecoins without an account or API key. Coinbase created it, and in 2026 it moved to the x402 Foundation at the Linux Foundation, which launched with 40 member organisations including Stripe, Visa, Mastercard, Google, and Cloudflare. A payment takes four steps:
- A client requests a resource, and the server replies 402 with the price, token, chain, and address.
- The client signs a payment for that amount and repeats the request with it attached.
- The server passes the payment to a facilitator, which verifies and settles it onchain.
- The server returns the resource with a receipt.
Coinbase's facilitator covers Base, Polygon, Arbitrum, Solana, and others, with the first 1,000 transactions a month free and $0.001 each after that. Circle runs one for USDC on Arc, Base, and Polygon PoS, and Stripe accepts x402 payments on Base and settles them to your Stripe balance in fiat.
Through the facilitators Paymentscan tracks, x402 settled $372,000 across 3.3 million payments in October 2026, about 11 cents each, down from a peak of $29.1 million in November 2025 (Paymentscan x402 data; the split by chain is in our comparison of blockchains for payments). The average payment is far below the $0.50 minimum Stripe sets for a charge, which is why x402 sits alongside a checkout rather than replacing one.
How to Choose a Blockchain Payment API
Start with what you need to do, then narrow down:
- Accept, send, or both. Stripe and PayPal are built mainly for accepting. If you also pay out to users or suppliers in crypto or stablecoins, look at BitPay, Triple-A, Coinbase Business, or CryptoProcessing. For bank payouts in other countries, see our stablecoin payout comparisons for the US, Europe, Asia, Latin America, Africa, and the Middle East.
- Fiat or stablecoins in the bank. If your costs are in USD or EUR, fiat settlement (Stripe, PayPal, BitPay, Triple-A) saves treasury work. If you pay suppliers onchain, keep stablecoins (Coinbase Business, Circle, Crossmint).
- The chains your customers use. Stripe doesn't accept USDT, and Coinbase Business accepts it only on Ethereum, while Triple-A lists TRON. Check the exact token and chain pairs before you launch in a market.
- Where your business is. Stripe's acceptance is generally available only to US businesses outside New York, and PayPal's only to US merchants. In the EU, BitPay, Triple-A, and Crossmint hold MiCA authorisations.
- Custody. Decide whether the provider may hold your funds. NOWPayments defaults new accounts to custodial processing, and Circle's Gateway is non-custodial.
- Total cost. Compare processing, conversion, network, and payout fees together. BitPay publishes the clearest rate card here; most others quote privately.
- Refunds and disputes. There are no chargebacks, so check how each API refunds and in what token: Stripe returns stablecoins to the original wallet, and PayPal refunds in PYUSD.
- Developer experience. Look for a testnet sandbox, signed webhooks, SDKs in your language, and plugins if you run WooCommerce or Magento.
If you also need bank accounts for your users, our comparison of stablecoin virtual accounts covers which providers offer them.
Which API to Start With
Start from where the money needs to end up. For fiat in the bank, Stripe, PayPal, BitPay, and Triple-A settle for you; to pay suppliers or users onchain, keep stablecoins with Coinbase Business, Circle, or Crossmint. If you sell API calls or data, add x402 next to your checkout rather than instead of it, and test refunds and webhook retries in a sandbox before launch.