# Checkbooks

[Checkbooks](/documentation/api/checkbooks) let you send a book of blank checks without working with a check manufacturer or operating a mailroom. Increase manufactures and mails the checkbook on your behalf, handles returned mail, and provides [positive pay](/documentation/positive-pay) for each check.

Increase offers a three-ring binder checkbook with 75 pages, three checks per page, for 225 checks in total. It is shipped via USPS to US addresses.

## Checkbook lifecycle

|                      |                                                                           |
| -------------------- | ------------------------------------------------------------------------- |
| `pending_submission` | The Checkbook is pending submission to the printer.                       |
| `pending_mailing`    | The Checkbook has been submitted to the printer and is pending mailing.   |
| `mailed`             | The Checkbook has been mailed.                                            |
| `stopped`            | The Checkbook has been stopped and its checks can no longer be deposited. |

### Creating a Checkbook

1. You call `POST /checkbooks` with the [details](/documentation/api/checkbooks#create-a-checkbook) about the account holder and recipient. A Checkbook is created with status `pending_submission`. A [Checkbook Check](/documentation/api/checkbook-checks) is created for every check number in the book.
2. When Increase submits the Checkbook to the printer, its status updates to `pending_mailing`.
3. When the Checkbook is shipped out by the printer, its status updates to `mailed`. Follow the Checkbook’s journey via its [tracking updates](/documentation/api/checkbooks#checkbook-object.tracking_updates).

Check numbers are assigned by Increase and are unique per Account Number. Multiple Checkbooks can be created under the same Account Number. Check numbers increment from the previous Checkbook and do not collide.

### Returned mail

Increase handles returned mail on your behalf. When a Checkbook is received at the return address, all of its checks are stopped.

## Checkbook Check lifecycle

|                      |                                                                                                                                                              |
| -------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| `pending_deposit`    | The check has not yet been deposited.                                                                                                                        |
| `deposited`          | The check has been deposited.                                                                                                                                |
| `stopped`            | The check has been stopped and can no longer be deposited.                                                                                                   |
| `requires_attention` | A rare status set when a check needs manual intervention from the Increase team. [More about requires\_attention](/documentation/requires-attention-status). |

Once the Checkbook is delivered, the recipient can write checks from it. Each check is tracked by a [Checkbook Check](/documentation/api/checkbook-checks) that was created with the Checkbook.

For each deposit attempt, an [Inbound Check Deposit](/documentation/inbound-check-deposits) is created with [`checkbook_check_id`](/documentation/api/inbound-check-deposits#inbound-check-deposit-object.checkbook_check_id) set to the matching Checkbook Check.

Increase then [evaluates the Inbound Check Deposit](/documentation/inbound-check-deposits#evaluating-deposit-attempts) with positive pay, and you can add your own [custom evaluation logic](/documentation/inbound-check-deposits#custom-evaluation-logic) before it resolves.

If the Inbound Check Deposit is accepted, the Checkbook Check transitions to `deposited`, a Transaction is created for the deposited amount, and funds leave the Account. If declined, the Checkbook Check remains `pending_deposit`.

## Evaluating deposit attempts

Every check in a Checkbook is covered by [positive pay](/documentation/positive-pay). A deposit is declined if the check number isn’t one you issued, if the check was stopped, or if it was already deposited. Increase can’t verify the amount, since it’s written by hand after the book is mailed.

You can layer your own rules on top with [custom evaluation logic](/documentation/inbound-check-deposits#custom-evaluation-logic). For example, you could enforce a maximum check amount per customer, or decline checks written to payees you don’t recognize.

## Stop payment requests

You can [stop a single Checkbook Check](/documentation/api/checkbook-checks#stop-a-checkbook-check) any time before it is deposited. Its status is updated to `stopped` and any later deposit attempt is declined.

You can also [stop an entire Checkbook](/documentation/api/checkbooks#stop-a-checkbook), for example if the book is lost in the mail or stolen. This stops every check in the book that has not yet been deposited and updates the Checkbook’s status to `stopped`. Checks that were already deposited are unaffected.