Offramp REST API Quickstart

In this guide, you will run a full USDC to USD offramp in the Staging environment. You will:

Confirm Offramp eligibility
Save the user’s payout method
Set up the wallet the user pays from
Create an Offramp order and read its deposit instructions
Broadcast the deposit and track the order to completion

Prerequisites

A server-side API key with the orders and payment-methods scopes (Crossmint console).
A user KYC-verified for Offramp. To verify a user, follow Import User KYC Data or the Identity quickstart. This quickstart uses userId:<USER_ID> in examples, but the API accepts any supported userLocator.
USDC to cash out. On staging, get testnet USDC from the Circle faucet.
Native gas tokens in the sender wallet to broadcast the deposit transaction (e.g., ETH on Base, SOL on Solana). This does not apply if the wallet sponsors gas.

Offramp uses Crossmint’s user KYC API. Contact sales to enable it for your project.

Confirm Offramp eligibility

Before creating an order, confirm that the user is verified for Offramp. Verification is asynchronous. Poll the user’s status with the Get Identity Verification endpoint until the offramp eligibility reads verified:

curl -X GET 'https://staging.crossmint.com/api/2025-06-09/users/<USER_LOCATOR>/identity-verification' \
  -H 'X-API-KEY: <YOUR_SERVER_API_KEY>'

<USER_LOCATOR> is the Crossmint user locator for the verified user, for example userId:<USER_ID> or email:<EMAIL>. See the Get Identity Verification API reference for all supported locator formats.

Example response

{
  "eligibility": [
    { "type": "onramp", "status": "verified" },
    { "type": "onramp-light", "status": "verified" },
    { "type": "offramp", "status": "verified" },
    { "type": "regulated-transfer", "status": "verified" }
  ]
}

Save the user's payout method

Save the user’s payout destination as a reusable payment method. The example below saves a US bank account. Sensitive fields are saved securely.See the Create Payment Method API reference for the full request schema and supported payment method types.

curl -X POST 'https://vault.staging.crossmint.com/api/unstable/payment-methods' \
  -H 'X-API-KEY: <YOUR_SERVER_API_KEY>' \
  -H 'Content-Type: application/json' \
  -d '{
    "type": "bank-account-us",
    "userLocator": "<USER_LOCATOR>",
    "bankAccount": {
      "accountNumber": "6349881141",
      "routingNumber": "026009593",
      "accountType": "checking",
      "bankName": "Chase",
      "bankAddress": { "line1": "420 Montgomery St", "city": "San Francisco", "stateOrRegion": "CA", "postalCode": "94104", "country": "US" },
      "currency": "usd",
      "country": "US",
      "entityType": "individual",
      "billing": { "name": "Alice Smith", "phone": "+13055551234", "address": { "line1": "701 S Miami Ave", "city": "Miami", "stateOrRegion": "FL", "postalCode": "33156", "country": "US" } }
    }
  }'

The response returns the saved payment method. Banks expose a masked accountSuffix (not last4). Save the paymentMethodId for the order step.

Example response

{
  "paymentMethodId": "d5e5c48a-7dec-44b1-8cf4-4615bf00c8fc",
  "default": false,
  "displayName": "Chase ••1141",
  "createdAt": "2026-06-17T21:25:56.542Z",
  "updatedAt": "2026-06-17T21:25:56.542Z",
  "type": "bank-account-us",
  "bankAccount": {
    "billing": {
      "name": "Alice Smith",
      "phone": "+13055551234",
      "address": { "line1": "701 S Miami Ave", "city": "Miami", "stateOrRegion": "FL", "postalCode": "33156", "country": "US" }
    },
    "bankName": "Chase",
    "accountSuffix": "1141",
    "currency": "usd",
    "country": "US",
    "entityType": "individual",
    "bankAddress": { "line1": "420 Montgomery St", "city": "San Francisco", "stateOrRegion": "CA", "postalCode": "94104", "country": "US" },
    "routingNumber": "026009593",
    "accountType": "checking"
  }
}

For listing, updating, and removing saved accounts, see Collect Bank Accounts.

Set up the payer wallet

Choose the wallet the user will send USDC from. The payer wallet must belong to the same verified user who owns the payout method.

Crossmint wallet
External wallet

Create a wallet owned by the verified user, with a server signer so your backend can sign. Ownership links the wallet to the user, so there is no separate linking step, and deposits are gasless.

import { createCrossmint, CrossmintWallets } from "@crossmint/wallets-sdk";

const wallets = CrossmintWallets.from(
  createCrossmint({ apiKey: process.env.CROSSMINT_SERVER_API_KEY })
);

const wallet = await wallets.createWallet({
  chain: "base-sepolia",
  owner: "userId:<USER_ID>",                                       // the user you verified
  recovery: { type: "server", secret: process.env.CROSSMINT_SIGNER_SECRET }, // server admin signer
  alias: "offramp-<USER_ID>",                                      // idempotent per (owner, alias)
});

owner ties the wallet to the verified user via their locator (e.g., userId:<USER_ID>). This ownership means no separate linking step is needed.
recovery sets a server signer from your CROSSMINT_SIGNER_SECRET, a secret you generate and keep on your server (the SDK derives the signing key from it locally). See Server Signer to create one.
alias is an optional label that makes the call idempotent, so re-running it with the same owner and alias returns the same wallet.

For all wallet options, see Create a Wallet. Then fund wallet.address with USDC and use it as the payer. No native gas is needed.

Link the user’s own wallet to the verified user. Make sure it holds USDC plus a little native gas for the deposit.

curl -X PUT 'https://staging.crossmint.com/api/2025-06-09/users/<USER_LOCATOR>/linked-wallets/<USER_WALLET_ADDRESS>' \
  -H 'X-API-KEY: <YOUR_SERVER_API_KEY>' \
  -H 'Content-Type: application/json' \
  -d '{ "chain": "base-sepolia" }'

Example response

{
  "address": "0xAa266270cf90FEEA9760617d9c7B5083e9f08984",
  "chain": "base-sepolia",
  "type": "external-wallet",
  "ownership": {
    "verified": false,
    "verificationChallenge": "crossmint.com wants you to sign in with your blockchain account..."
  }
}

Each wallet links to one user, so use a separate wallet per user. The response returns an ownership challenge; on staging you do not need to sign it to proceed.

Create an offramp order

Create the order with the amount of USDC to cash out (exact-in), the chain you will pay from, and the saved bank account as the recipient. Use the payer wallet from the previous step as payerAddress.

curl -X POST 'https://staging.crossmint.com/api/2022-06-09/orders' \
  -H 'X-API-KEY: <YOUR_SERVER_API_KEY>' \
  -H 'Content-Type: application/json' \
  -d '{
    "recipient": { "paymentMethodId": "<PAYMENT_METHOD_ID>" },
    "payment": { "method": "base-sepolia", "currency": "usdc", "payerAddress": "<USER_WALLET_ADDRESS>", "receiptEmail": "alice@example.com" },
    "lineItems": { "currencyLocator": "fiat:usd", "executionParameters": { "mode": "exact-in", "amount": "1" } }
  }'

The order comes back in the payment phase. Its deposit instructions live under order.payment.preparation: a ready to broadcast serializedTransaction (a USDC transfer that already carries the matching memo in its calldata) and the same memo in transactionParameters.memo. Keep the order.orderId.

Example response (201)

{
  "clientSecret": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJvcmRlcklkZW50aWZpZXIiOiI0MGY0OTgxMi0xMjNiLTRkMTAtYmRhZS01NjFlNGVkMmI5OTAiLCJjb2xsZWN0aW9uSWQiOiJjMjI0MGQ2Yy00NGM0LTQ1OTMtOGM4Yy1jZDRkYzJiZjE4MzUiLCJpYXQiOjE3ODE3MzI5MzQsImV4cCI6MTc4MTgxOTMzNH0.Na-AHOlge6-pYhpMszvITqe3ry49fk-o66i3gfz9a3I",
  "order": {
    "orderId": "40f49812-123b-4d10-bdae-561e4ed2b990",
    "phase": "payment",
    "locale": "en-US",
    "lineItems": [
      {
        "metadata": {
          "name": "USD",
          "description": "United States Dollar",
          "imageUrl": "https://www.crossmint.com/assets/ui/flags/us.svg"
        },
        "quote": {
          "status": "valid",
          "charges": {
            "unit": { "amount": "1", "currency": "usdc" },
            "fees": { "type": "exact", "amount": "0.002", "currency": "usdc" }
          },
          "totalPrice": { "amount": "1", "currency": "usdc" },
          "quantityRange": { "lowerBound": "1", "upperBound": "1" }
        },
        "delivery": {
          "status": "awaiting-payment",
          "recipient": {
            "locator": "paymentMethodId:d5e5c48a-7dec-44b1-8cf4-4615bf00c8fc",
            "paymentMethodId": "d5e5c48a-7dec-44b1-8cf4-4615bf00c8fc"
          }
        },
        "executionMode": "exact-in",
        "callData": {
          "mode": "exact-in",
          "amount": "1",
          "outFiatCurrency": "usd",
          "effectiveAmount": "0.998"
        },
        "quantity": 1
      }
    ],
    "quote": {
      "status": "valid",
      "quotedAt": "2026-06-17T21:48:49.059Z",
      "expiresAt": "2026-06-17T21:58:49.059Z",
      "totalPrice": { "amount": "1", "currency": "usdc" }
    },
    "payment": {
      "status": "awaiting-payment",
      "method": "base-sepolia",
      "currency": "usdc",
      "preparation": {
        "chain": "base-sepolia",
        "payerAddress": "0xAa266270cf90FEEA9760617d9c7B5083e9f08984",
        "serializedTransaction": "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",
        "transactionParameters": {
          "amount": "1000000",
          "memo": "------BEGIN MEMO------eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJub25jZSI6IjMwMWVmZTg4LWU2MjItNDM0YS04NDY2LTgwNWQzNWQ4ZTFjYiIsIm9yZGVySWRlbnRpZmllciI6IjQwZjQ5ODEyLTEyM2ItNGQxMC1iZGFlLTU2MWU0ZWQyYjk5MCIsImlhdCI6MTc4MTczMjkyOX0.Zokhvn0bnyjLsOpuJyzQ1fnsFZHkM6Em9erLzfxWdCI------END MEMO------"
        }
      },
      "receiptEmail": "alice@example.com"
    },
    "legal": {
      "requirements": [
        { "display": "show-checkbox", "type": "crossmint-terms-of-service", "url": "https://staging.crossmint.com/legal/crossmint-terms-of-service/TRGUSAALLALLALL" },
        { "display": "show-text", "type": "crossmint-privacy-policy", "url": "https://staging.crossmint.com/legal/crossmint-privacy-policy/ALLALLALLALLALL" }
      ]
    }
  }
}

Broadcast the deposit

The order’s payment.preparation.serializedTransaction is a prepared USDC transfer that already carries the order’s memo in its calldata. Sign and broadcast it from the payer wallet. Crossmint matches the deposit to the order by that memo automatically, so no further call is needed.

Crossmint wallet
External wallet

Sign and send it from the wallet you created, using its server signer (a gasless transaction):

import { EVMWallet } from "@crossmint/wallets-sdk";
import { parseTransaction } from "viem";

// `wallet` from the setup step, `order` from the create-order step
await wallet.useSigner({ type: "server", secret: process.env.CROSSMINT_SIGNER_SECRET });

const { to, data } = parseTransaction(order.payment.preparation.serializedTransaction);
await EVMWallet.from(wallet).sendTransaction({ to, value: 0n, data });

See Send a Transaction for signer setup and other platforms.

Sign and broadcast it with the payer’s key using viem:

import { createWalletClient, http, parseTransaction } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { baseSepolia } from "viem/chains";

const account = privateKeyToAccount(process.env.PAYER_PRIVATE_KEY);
const walletClient = createWalletClient({ account, chain: baseSepolia, transport: http() });

// `order` from the create-order step
const { to, data } = parseTransaction(order.payment.preparation.serializedTransaction);
const hash = await walletClient.sendTransaction({ to, value: 0n, data });

Track the order

Poll the order until the payout completes, or subscribe to webhooks (see Manage Orders).

curl -X GET 'https://staging.crossmint.com/api/2022-06-09/orders/<ORDER_ID>' \
  -H 'X-API-KEY: <YOUR_SERVER_API_KEY>'

GET returns the order flat at the top level (no order wrapper and no clientSecret, unlike the create response). Watch phase, which moves from payment to completed, along with payment.status and lineItems[0].delivery.status. When it completes, payment.received is populated with the matched on-chain transaction.

Example response (completed)

{
  "orderId": "40f49812-123b-4d10-bdae-561e4ed2b990",
  "phase": "completed",
  "locale": "en-US",
  "lineItems": [
    {
      "metadata": {
        "name": "USD",
        "description": "United States Dollar",
        "imageUrl": "https://www.crossmint.com/assets/ui/flags/us.svg"
      },
      "quote": {
        "status": "valid",
        "charges": {
          "unit": { "amount": "1", "currency": "usdc" },
          "fees": { "type": "exact", "amount": "0.002", "currency": "usdc" }
        },
        "totalPrice": { "amount": "1", "currency": "usdc" },
        "quantityRange": { "lowerBound": "1", "upperBound": "1" }
      },
      "delivery": {
        "status": "completed",
        "recipient": {
          "locator": "paymentMethodId:d5e5c48a-7dec-44b1-8cf4-4615bf00c8fc",
          "paymentMethodId": "d5e5c48a-7dec-44b1-8cf4-4615bf00c8fc"
        }
      },
      "executionMode": "exact-in",
      "callData": {
        "mode": "exact-in",
        "amount": "1",
        "outFiatCurrency": "usd",
        "effectiveAmount": "0.998"
      },
      "quantity": 1
    }
  ],
  "quote": {
    "status": "valid",
    "quotedAt": "2026-06-17T21:48:49.059Z",
    "expiresAt": "2026-06-17T21:58:49.059Z",
    "totalPrice": { "amount": "1", "currency": "usdc" }
  },
  "payment": {
    "status": "completed",
    "method": "base-sepolia",
    "currency": "usdc",
    "preparation": {
      "chain": "base-sepolia",
      "payerAddress": "0xAa266270cf90FEEA9760617d9c7B5083e9f08984",
      "serializedTransaction": "0x02f9018e83014a348083171dd9837ec1d582c3be94036cbd53842c5426634e7929541ec2318f3dcf7e80b90164a9059cbb000000000000000000000000bd1af733aed9d9f472a15a4ce13f42097bbc9eaa00000000000000000000000000000000000000000000000000000000000f42400a0a2d2d2d2d2d2d424547494e204d454d4f2d2d2d2d2d2d65794a68624763694f694a49557a49314e694973496e523563434936496b705856434a392e65794a756232356a5a534936496a4d774d57566d5a5467344c5755324d6a49744e444d30595330344e4459324c5467774e57517a4e5751345a54466a59694973496d39795a4756795357526c626e52705a6d6c6c63694936496a51775a6a51354f4445794c5445794d3249744e4751784d4331695a47466c4c5455324d5755305a575179596a6b354d434973496d6c68644349364d5463344d54637a4d6a6b794f58302e5a6f6b68766e30626e796a4c734f70754a797a5131666e73465a486b4d36456d3965724c7a6678576443492d2d2d2d2d2d454e44204d454d4f2d2d2d2d2d2dc0",
      "transactionParameters": {
        "amount": "1000000",
        "memo": "------BEGIN MEMO------eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJub25jZSI6IjMwMWVmZTg4LWU2MjItNDM0YS04NDY2LTgwNWQzNWQ4ZTFjYiIsIm9yZGVySWRlbnRpZmllciI6IjQwZjQ5ODEyLTEyM2ItNGQxMC1iZGFlLTU2MWU0ZWQyYjk5MCIsImlhdCI6MTc4MTczMjkyOX0.Zokhvn0bnyjLsOpuJyzQ1fnsFZHkM6Em9erLzfxWdCI------END MEMO------"
      }
    },
    "received": {
      "chain": "base-sepolia",
      "txId": "0xc9537a0e4ee4794101514d30418bd20f09cf66c3ce86b82b0be916489a338e85",
      "amount": "1",
      "currency": "usdc"
    },
    "receiptEmail": "alice@example.com"
  }
}

On staging the payout is simulated. To pay out to a bank in production, see Launch in Production.

Troubleshooting

Enable KYC for your project

Offramp’s KYC endpoints are turned on per project. Contact sales to enable KYC for yours. The response project not configured to support the users KYC endpoints is the signal to reach out.

Use a userId locator

The user and KYC endpoints expect a userId: locator, for example userId:alice-123. The email: and other locator formats apply to Crossmint auth wallets, so use userId: for these endpoints.

Wait for verification before ordering

Verification is asynchronous. Poll GET /users/{userId}/identity-verification until the offramp eligibility reads verified, then create the order.

Set the Crossmint wallet owner to the verified user

Create the payer wallet with owner: "userId:<the verified user>". With no owner it is company-owned, which the order does not accept. A wallet’s owner is set once at creation.

The deposit matches automatically

After you broadcast the prepared transaction, Crossmint matches it to the order by its memo, so the deposit is already assigned. You do not need to call POST /orders/{orderId}/payment.

REST API Quickstart

Prerequisites

Troubleshooting

Next steps

Manage Orders

How It Works

​Prerequisites

​Troubleshooting

​Next steps

Manage Orders

How It Works

Prerequisites

Troubleshooting

Next steps