# How a crypto payment gateway works, from invoice to settlement

> A crypto payment gateway does for blockchain payments what a card gateway does for cards: it turns "a customer wants to pay" into a confirmed, reconciled payment your systems can trust. Here is what happens at each step.

Updated 2026-09-30 · Payaries · https://www.payaries.com/guides/how-a-crypto-payment-gateway-works

## What a gateway is — and isn't

A wallet stores keys. An exchange trades assets. A payment gateway sits between your checkout and the [blockchain](https://www.payaries.com/blog/what-is-blockchain): it creates a payment request, watches the chain for the customer's transfer, decides when it counts as paid, tells your backend, and gets the funds to where you can use them.

The hard parts are operational rather than cryptographic — watching several networks reliably, handling partial, late and duplicate payments, and keeping a ledger that always matches the chain. That is what you buy instead of building.

## The six steps

1. **Create an invoice.** Your backend asks the gateway for a payment of, say, 49.99 USD in USDT on Tron. The gateway converts it, locks the rate and returns a deposit address that belongs to this invoice alone.
2. **Show the customer the address.** Your checkout displays the address and amount, usually as text plus a QR code, with a countdown to expiry.
3. **The customer pays.** They send the asset from any wallet or exchange. The gateway's chain listener sees the transaction and the invoice moves from `pending` to `detected`.
4. **Wait for confirmations.** One block isn't proof of payment; the invoice sits in `confirming` until the network's required number of confirmations is reached. See [crypto payment confirmations](https://www.payaries.com/guides/crypto-payment-confirmations).
5. **Confirm and notify.** The invoice becomes `confirmed`, the merchant's ledger is credited and a signed webhook tells your backend to release the order.
6. **Settle and withdraw.** The deposit is swept from the one-time address to the merchant's wallet (`forwarding`, then `settled`), after which the balance can be withdrawn to any address.

## Why every invoice gets its own address

With one address per invoice, the gateway can attribute an incoming transfer to an order without asking the customer to paste a memo or transaction hash. The amount, the network and the address together identify the payment, which is also what makes [underpayments](https://www.payaries.com/guides/handle-underpaid-and-late-crypto-payments) and late payments detectable rather than ambiguous.

## Where the money sits

That depends on the provider. Payaries holds the funds for you: each merchant has a dedicated wallet per chain — never pooled with other merchants — and the on-chain balance can be checked against a block explorer. The trade-offs are covered in [managed vs self-held payment gateways](https://www.payaries.com/guides/custodial-vs-non-custodial-payment-gateway).

## What integration looks like

For a developer it is three pieces: a server call to create the invoice, a checkout that displays the address, and a webhook endpoint that marks the order paid. The [crypto payment API](https://www.payaries.com/crypto-payment-api) page shows each with real requests.

## Questions

**What is a crypto payment gateway?**
A service that creates payment requests for blockchain transfers, watches the network for the customer's payment, decides when it is confirmed, notifies the merchant's backend and gets the funds to the merchant. It is to crypto what a card gateway is to card payments.

**How is a payment gateway different from a crypto wallet?**
A wallet stores keys and sends or receives funds. A gateway adds the payment layer around that: invoices, per-order deposit addresses, confirmation tracking, webhooks, a ledger and settlement.

**Why does a gateway wait for confirmations?**
A transaction seen on the network can still be dropped or reorganised shortly after. Waiting for several confirmations makes it safe to treat the payment as final.

## Try it

See it run on a real invoice: [Payaries — www.payaries.com](https://www.payaries.com/signup). Payaries is a multi-chain crypto payment gateway — https://www.payaries.com

## Keep reading

- https://www.payaries.com/blog/what-is-a-crypto-payment-gateway — What is a crypto payment gateway?
- https://www.payaries.com/guides/crypto-payment-confirmations — Crypto payment confirmations, explained for merchants
- https://www.payaries.com/crypto-payment-api — A crypto payment API that behaves like the rest of your stack
- https://www.payaries.com/usdt-payment-gateway — Accept USDT payments on Ethereum, BNB Smart Chain, Polygon, Arbitrum, Tron and more
- https://www.payaries.com/guides/custodial-vs-non-custodial-payment-gateway — Managed vs self-held crypto payment gateways
- https://www.payaries.com/solutions/web3 — A crypto payment gateway for Web3 companies
- https://www.payaries.com/solutions/ecommerce — Accept crypto payments in your online store, SaaS or marketplace