Fiat Onramps

Surplus Intelligence supports fiat-to-USDC wallet funding through buyer dashboard onramps. USDC lands in the buyer's Base wallet, then the normal marketplace flow handles approvals, API-key usage, x402 payments where applicable, and per-request seller settlement.

Live Funding Options

  • Card top-up (Stripe) — fund your balance directly with a card via POST /v1/payments/topup; check it with GET /v1/payments/balance
  • Coinbase Onramp — Apple Pay, debit card, Coinbase account
  • Peer / ZKP2P — Venmo, Revolut, Cash App, PayPal, Wise, Zelle
  • MoonPay via Privy — card, Apple Pay, Google Pay
  • Manual Base USDC transfer to the buyer wallet

How It Works

1. Sign in and open the buyer funding flow.

2. Either top up your balance with a card via POST /v1/payments/topup (Stripe), choose an onramp, or copy your wallet address for a direct Base USDC transfer.

3. Fund the wallet with USDC on Base (onramp/transfer paths).

4. Approve marketplace spend.

5. Use your Surplus API key or x402-compatible client; sellers are paid on-chain per request.

Enterprise Card Billing

For card-funded balances, Stripe top-up (POST /v1/payments/topup) credits your account and GET /v1/payments/balance reports the current balance. Stripe Billing Credits + Meters remains a possible enterprise invoicing path, but live onramps already deliver Base USDC and are generally cheaper than a Stripe + stablecoin bridge flow.