01
Create the order
Create a one-time order from your server with the API, then share its hosted payment link.
Order + exact amount Non-custodial stablecoin checkout
Accept stablecoin payments.
Your books close themselves.
Start with one USDC or USDT address you already control. Customers pay through a clear hosted checkout, funds go directly to your wallet, and every payment arrives already reconciled.
No custody No custodial account approval Direct to your wallet
You remain responsible for your own tax, sanctions, and customer due-diligence obligations.
MAINPAY CHECKOUTSecure payment
ORDER2,500 AI credits
$25.00U
PAY WITHUSDC on Base
Exact amountSEND EXACTLY25.000042 USDC
0x71E4…9A20 Watching for paymentFunds go directly to Atlas AI
Payment reconcileduser_42 · order_1842 · books ready
One product, two doors
Checkout brings the payment in.Reconciliation closes it out.From order to books
Three steps. One complete payment record.
No second system and no spreadsheet handoff after checkout.
02
Your customer pays
They scan the QR code or connect their own wallet, review the exact transfer, and sign it themselves.
QR or connect wallet03
Receive and reconcile
Funds land in your wallet. MainPay confirms the transfer, sends a signed webhook, and matches the books.
Paid + reconciledThe non-custodial wedge
Your customer pays you.
MainPay never sits in the middle.
Connect a public receiving address. Your customer signs from their wallet and the stablecoins settle directly to yours. MainPay observes and records the transfer; it never holds keys or moves funds.
Your wallet, your keys
No pooled balance, payout wait, or MainPay-controlled account.
No KYC onboarding gate
No MainPay custody or KYC onboarding step sits between your wallet and a test checkout.
No card chargebacks
Stablecoin transfers settle on-chain. Refunds are initiated by you from your own wallet—MainPay cannot pull funds back.
The built-in advantage
Not just checked out.
Already reconciled.
Every MainPay order carries its customer, amount, wallet, transaction, and reference into one operational record. Revenue is matched as it arrives, exceptions are flagged, and accountant-ready CSV exports support QuickBooks or Xero.
- Exact on-chain transfer linked to the order
- Underpayments, overpayments, and unknown senders surfaced
- Accountant-ready CSV and locked close records
REVENUE RECORDAll matched
Received$8,475.00
Close-readyAArc & Co.INV-042
USDC · Base$4,800.00 ReconciledNNova SystemsORDER-1842
USDT · TRON$2,500.00 ReconciledSStudio TenINV-040
USDC · Ethereum$1,175.00 ReconciledExact amounts · wallet evidence · signed eventsExport CSV →
Built for developers
Create server-side.
Open checkout anywhere.
Keep your API key on the server, return only the hosted URL, then fulfill from a verified t=,v1= webhook.
checkout.tsServer only
const response = await fetch(
"https://api.mainpay.com/v1/invoices",
{
method: "POST",
headers: {
"X-API-Key": process.env.MAINPAY_API_KEY,
"Idempotency-Key": crypto.randomUUID(),
"Content-Type": "application/json"
},
body: JSON.stringify({
fiat_amount: "25.00",
asset: "USDC",
network: "base",
receiving_account_id: process.env.MAINPAY_WALLET_ID,
customer_name: "user_42",
client_reference_id: "user_42"
})
}
);
const order = await response.json();
// Return only this public URL to your browser.
return order.hosted_url;Honest scope
One-time payments now.
Credits when the product repeats.
MainPay supports one-time orders and prepaid credit top-ups today. Your app owns and grants the credit balance after a verified paid event.
One-time checkout
Create an order, collect one wallet-signed transfer, and fulfill from the paid webhook.
Prepaid credits
Use a one-time credit_topup order, then grant credits in your own database.
Automatic renewal
No auto-charge subscriptions. A non-custodial checkout cannot pull the next payment from a customer's wallet.
Accept, match, close