FAQ.

What does Settle actually do?

It’s a stablecoin payment rail. Customer pays an invoice in USDC on Base; the router contract atomically splits the payment 99.5% to the merchant and 0.5% to Settle in one on-chain transaction. We are not a wallet, not a custodian, not a fiat gateway, not a chargeback service.

How much does it cost?

0.5% per successful transaction. No monthly fee, no setup fee, no minimum, no rolling reserve, no chargeback fee, no cross-border surcharge. The customer pays network gas. See Fees.

Can I refund a customer?

Not through Settle. Settlement is atomic and final — by the time we know about a payment, funds are already in your wallet. If you want to refund, send the funds back yourself from the same wallet. We display this loudly on every checkout, in plain text, before the customer signs.

What about chargebacks?

There are no chargebacks. The customer signs a transaction with their own keys; once mined, no third party can reverse it. This is the main reason merchants in industries Stripe rejects use us. See Settlement.

Do I have to do KYC?

No KYC for the merchant beyond GitHub OAuth and a payout-address signature challenge. We screen the payout address against OFAC SDN and Chainalysis sanctions; that’s it. We do not collect government IDs, business registration documents, or bank statements.

What chains and currencies do you support?

• USDC on Base.

Which jurisdictions can I sell to?

Customers in OFAC-sanctioned jurisdictions or matching the SDN list cannot complete checkout — the page refuses to load before any signature. Beyond that we don’t geofence. You as the merchant are responsible for whatever local rules apply to your business and your customers; we provide the rail, not the legal opinion.

Is there a sandbox?

Test mode. Separate API keys (sk_test_…), the test router on Base Sepolia, and full webhook delivery. Use simulate_payment to flip an invoice to paid and fire the webhook without an on-chain transaction.

What if the customer underpays?

For Path A (connect wallet), the customer signs an authorization for exactly the invoice amount — there is no underpayment shape. For Path B (pay-with-address), the v2 forwarder will fire invoice.underpaid if the deposit comes in low; the v1 path treats anything below the threshold as unpaid until the difference arrives.

How fast is settlement?

Base, ~2 seconds. Wall-clock from customer signature to invoice.paid firing. See finality thresholds.

What's the per-transaction limit?

$500,000 USD-equivalent. Hard cap, set in the router contract. Larger sales must split into multiple invoices.

How do I get help?

Email support@settleco.com. We respond within 24 hours on weekdays, 48 hours on weekends. For security issues, email security@settleco.com — that’s monitored continuously and triaged within 4 hours. Bug bounty details at security.settle.xxx.