---
title: "Get USDC Authorization Message (EVM only)"
method: POST
path: "/checkout/evm/usdc-authorization"
tags: ["checkout"]
---

# Get USDC Authorization Message (EVM only)

`POST /checkout/evm/usdc-authorization`

Gets the USDC authorization message to be signed by the customer for dual-source payments.
The signed message allows the customer's USDC to be used alongside credit card payment.

This is only necessary for EVM chains when using customer USDC + credit card payment.

## Headers

- `x-coinflow-auth-session-key` string, required

## Request body

- GetUsdcAuthorizationBody — Request body for getting USDC authorization message
  - `amount` Cents, required
    - `cents` integer, required
  - `paymentId` string — Optional payment ID for generating unique nonce

## Response `200`

Ok

- GetUsdcAuthorizationResponse — Response for USDC authorization message
  - `message` string, required — EIP-712 message to sign
  - `messageData` GetUsdcAuthorizationResponseMessageData, required — Structured message data for transparency
    - `nonce` string, required
    - `validBefore` string, required
    - `validAfter` string, required
    - `value` string, required
    - `to` string, required
    - `from` string, required

---

[API](https://skmtc.net/coinflow/apis/api-reference.md) · [All operations](https://skmtc.net/coinflow/apis/api-reference/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/coinflow/api-reference/versions/3f6a046fbb34/schema)