How to evaluate a crypto payment gateway without the landing-page fog

“Best crypto payment gateway” lists are usually affiliate tables. Here is a buyer checklist that does not care who paid for a badge.

Decide the job

• Checkout: hosted button, low AOV, you need conversion. Custody is common. Fiat off-ramp might be the actual product.
• B2B invoices: unique addresses, rate locks, webhooks into ERP. Custody is a bug unless you explicitly want a balance account.
• On-chain native: you already have a treasury. You want matching, not a new bank.

Settlematic Gateway is the third job, and it is sandbox, not a production ranking. Collect (invoicing) is live. Do not read this as “we won a shootout.”

Criteria that survive a year

1. Key control — who signs the first outbound from the pay-in address.
2. Address uniqueness — pooled vs per-invoice / per-intent.
3. Finality policy — per-chain, not a single “1 confirmation” for Bitcoin and Polygon.
4. Webhook crypto — HMAC, timestamp, replay window. Unsigned JSON is a toy.
5. Asset honesty — USDC on which chains, actually, in production. Settlematic’s live Collect path includes USDC/USDT/EURC/ETH/BTC across Ethereum, Polygon, BSC, Tron, Bitcoin, plus native SOL on Solana. USDC-on-Solana is not a production payment path for us today. If a competitor claims six chains, ask for a tx on each.
6. Failure modes — underpay, overpay, wrong chain, expired rate lock. If the docs only show happy path, the support queue is the product.

Integration shape

A gateway that only exists as a WordPress plugin is a different market than an API + webhook + MCP for operators. Pick the surface your team will actually run at 11pm.

If you want invoices, start at settlematic.com. Canonical essay: best crypto payment gateway.