# External Accounts

[External Accounts](/documentation/api/external-accounts) represent accounts at financial institutions other than Increase. Rather than re-entering a routing number and account number every time you send money, you can store these details once as an External Account and reference them when initiating [transfers](/documentation/transactions-transfers).

Some developers use Increase as the storage for sensitive details like these account and routing number pairs. This is sometimes called a "tokenized" account number: when you store the details, Increase returns an opaque ID that can be used for future transfers, in other words: the token.

## Creating an External Account

You [create an External Account](/documentation/api/external-accounts#create-an-external-account) by providing the destination `routing_number` and `account_number`, along with a `description` for display purposes. You can optionally specify the `funding` type (`checking`, `savings`, or `other` — defaults to `checking`) and the `account_holder` (`business` or `individual`).

The account number isn't validated with the bank it belongs to; if it's incorrect, you'll find out when the resulting transfer is returned by the receiving bank.

## Using an External Account

Once created, an External Account can be referenced by its `id` (e.g., `external_account_ofiz7n0unkkcg0p4xhmm`) when initiating transfers. For example, when [creating an ACH Transfer](/documentation/api/ach-transfers#create-an-ach-transfer), you can pass `external_account_id` instead of `routing_number` and `account_number`. The same `id` can be reused across any of the supported transfer types.

## Status

| Status     | Description                                                         |
| ---------- | ------------------------------------------------------------------- |
| `active`   | The External Account can be used as a destination for transfers.    |
| `archived` | The External Account is archived and won't appear in the Dashboard. |

You can move an External Account to `archived` by [updating it](/documentation/api/external-accounts#update-an-external-account) with `status: archived`.

## Updating an External Account

You can update an External Account's `description` and `status` at any time via the [update endpoint](/documentation/api/external-accounts#update-an-external-account). The `routing_number` and `account_number` are immutable; if the destination changes, create a new External Account.