How fiat-quoted crypto payments work under the hood

Fiat-quoted crypto invoicing sounds contradictory until you separate denomination from settlement. The invoice amount is denominated in USD, EUR, or GBP because that is how your contracts, taxes, and books are structured. Settlement happens in crypto because that is how your client wants to pay. Settlematic bridges the two with quoted crypto amounts, rate validity windows, and deterministic reconciliation.

Quote generation at send-time

When you send an invoice, Settlematic snapshots exchange rates for each allowed asset and computes crypto amounts that satisfy the fiat total (including tax and discounts). The client sees both: '$4,200.00 due' and '≈ 4,198.50 USDC on Polygon' with a countdown for quote validity — typically 15 minutes in v1.

If the quote expires before payment, the client refreshes the page for updated amounts. This protects merchants from stale prices during volatile markets while keeping UX simple — no manual renegotiation in email.

Per-invoice asset allowlists

You control which assets appear at checkout per invoice. A EU client might get USDC on Polygon and ETH; a treasury-conscious merchant might allow only stablecoins. Restricting assets reduces operational surprise and narrows reconciliation surface area.

Unique deposit addresses per asset

Each allowed asset receives a unique deposit address for that invoice. When funds arrive, matching is address-based — not memo-field gymnastics. This is critical for Bitcoin and EVM chains where shared addresses would make invoice-level reconciliation ambiguous.

Partial payments and balance due

Optional partial payment support decreases balance due with each confirmed tranche. Status moves to PARTIALLY_PAID until fiat-equivalent remaining hits zero within tolerance. Underpaid and overpaid states surface clearly on merchant and client views so support does not guess.

Tolerance bands account for rate movement between quote and confirmation. Document your policy for clients — most disputes come from assuming spot rates are frozen indefinitely.

Confirmations before sweep

Detection is not settlement. Workers wait for configurable confirmation thresholds per network before marking CONFIRMED and enqueueing sweeps. Bitcoin mainnet might wait for more blocks than Polygon USDC; policy reflects reorg risk and your finance team's appetite.

What we do not do in v1

Settlematic does not auto-convert crypto to fiat bank deposits in v1. You receive on-chain assets (or route them through conversion flows to other crypto). Off-ramp to wire is your choice of exchange or banking partner. This keeps regulatory and custody boundaries clear.

Understanding this model helps you explain checkout to clients and configure treasury realistically — fiat clarity for contracts, crypto flexibility for settlement.