Get the fast transfer allowance

Check the remaining Fast Transfer allowance for USDC transfers

This how-to shows you how to retrieve the remaining Fast Transfer allowance using the CCTP API. The Fast Transfer allowance is Circle’s mechanism for backing faster-than-finality USDC transfers before burns reach hard finality on source chains.

Prerequisites

Before you begin, ensure you have:

• Installed cURL on your development machine

Get the Fast Transfer allowance

Call the GET /v2/fastBurn/USDC/allowance endpoint to retrieve the current remaining Fast Transfer allowance.

Example request

Shell

curl --request GET \
  --url 'https://iris-api-sandbox.circle.com/v2/fastBurn/USDC/allowance' \
  --header 'Accept: application/json'

Response

{ "allowance": 99999999225.24174, "lastUpdated": "2025-12-02T13:17:02.453Z" }

The response includes:

• allowance: The remaining Fast Transfer allowance in USDC units
• lastUpdated: The UTC timestamp when the allowance was last updated

Fast Transfer allowance details:

• The allowance represents the total value of USDC that can be minted through Fast Transfer before related burns on source chains reach hard finality.
• When you initiate a Fast Transfer, the burn amount temporarily debits the allowance.
• Once the burn reaches finality on the source chain, the corresponding amount is credited back to the allowance.
• If the allowance is insufficient for your transfer, you should either wait for the allowance to replenish or use Standard Transfer instead.