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.