Explanatory and how-to content
API Reference
Technical documentation
Release notes
Manage your account
Service status

Deprecated unique identifier field

The unique_identifier parameter to create Transfers was renamed to Idempotency-Key in January 2024. The functionality of unique_identifier is now available across all Increase API objects.

Learn more about Increase idempotency.

We'll still respect the value of unique_identifier if your implementation sends that data on POST requests for:

  • Account Transfers
  • ACH Transfers
  • Check Transfers
  • Real-Time Payments Transfers
  • Wire Transfers

We recommend using the HTTP header based implementation and using Idempotency across all requests you send to Increase.