# ACH reversals

Nacha has a number of conventions that have reached varying degrees of codification. One is reversals—reclaiming funds from an erroneous transfer. Importantly, reversals aren’t a network primitive; they’re regular transfers and therefore can be returned.

For reversals, Nacha requires all fields are the same as the original ACH transfer except for the Company Entry Description (which must be set to `REVERSAL`). A reversal must be sent within 24 hours of noticing the error, and no later than 5 business days from the settlement date of the original ACH transfer. Additionally, reversals will only be accepted for the following errors:

- A duplicate payment
- Specifying an incorrect recipient
- Specifying an incorrect amount
- Sending a Debit earlier than intended
- Sending a Credit later than intended

## How reversals work at Increase

If you need to send a reversal, you can duplicate your initial ACH Transfer with the same `account_number`, `routing_number`, `statement_descriptor`, and `amount` (with the opposite sign). However, you’ll need to include the `company_entry_description` with a value of `REVERSAL`. Because reversals are sent as separate ACH transfers, they will not be associated with the original Transfer object.

## Other Conventions

Other Nacha conventions with varying degrees of formality are child support payments, tax payments, and corporate trade exchange data.