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# v1.6.5

See below for our latest API changes. This release makes a **breaking change to account closure**: an account must now have a zero balance before it can be closed. It also adds four **market reference rates** for floating-rate accounts and raises some depositor field limits. We recommend reviewing this page closely before beginning development or upgrading to a new API version.

## ⚠️ Breaking Changes

* **Accounts must have a zero balance, including pending transactions, before they can be closed.** `DELETE /digital-banking/v1/accounts/{account_id}` now returns `400` when the account's `pending_balance` is not zero. Before this release, the endpoint withdrew the remaining balance as part of the close. An integration that closes funded accounts in one call will now get an error, and the account stays open. To close a funded account, first withdraw the remaining funds through your integration or a booked withdrawal so that `pending_balance` is zero, then call Close Account. This is in effect now.

## Updated Endpoints

* **`DELETE /digital-banking/v1/accounts/{account_id}`** (Close Account)
  * Returns `400` when the account's `pending_balance`, which includes pending transactions, is not zero. See Breaking Changes above.
  * If an account still holds a balance on its closure date, for example because the withdrawal that emptied it did not settle, the account stays open and its closure moves to the next closure date.

* **`POST /digital-banking/v1/depositors`** (Create Depositor) and **`PATCH /digital-banking/v1/depositors/{depositor_id}`** (Update Depositor)
  * `institution_depositor_id` now accepts up to 256 characters (was 64).
  * On Update Depositor, `account_officer` now accepts up to 128 characters (was 64), the same limit as Create Depositor.
  * ⚠️ On Create Depositor, `tin` must be properly formatted (nine digits, dashes allowed) and cannot be left empty. Requests with an empty or badly formatted `tin` are rejected.

## Schema Changes

* **`ReferenceRateType`**
  * Added `SOFR_OVERNIGHT` (Overnight SOFR), `CMT_1M` and `CMT_6M` (1- and 6-month Constant Maturity Treasury), and `IORB` (Interest on Reserve Balances). You can use them as the `rate_index_type` for floating-rate accounts and pricing-group rate tiers. If you validate enums strictly, add these values.

* **`RateConfiguration`**
  * Added `MIXED`, which describes pricing groups that combine fixed and floating tiers. `AccountResponse.rate_configuration` never returns it.