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# Subaccounts

> Manage reputation, activity, reports, and quotas across different senders under a single account.

## The basics

If you send emails on behalf of different clients or if you run multi-tenant systems to separate sending for different users, you can use subaccounts to manage reputation, activity, reports, and quotas across different senders under a single Mailchimp Transactional account.

This documentation will give you all the information you need to create and manage subaccounts, but to walk through the process with code samples, check out the [Manage Different Users with Subaccounts](/developer/transactional/guides/manage-different-users-subaccounts) guide.

> **Note**
>
> **Note**: If you’re looking for a way to segment your messages without creating separate subaccounts, you can use [tags or other metadata](/developer/transactional/docs/tags-metadata) to manage sending.

## Create a subaccount

You can create a subaccount with the web app or via the Transactional API.

In the app:

1. Navigate to the [**Outbound**](https://mandrillapp.com/activity) section and select [**Subaccounts**](https://mandrillapp.com/subaccounts)
2. Click\*\* + Create a Subaccount\*\*
3. Choose a unique identifier for the subaccount, like a unique ID from your own application or database. You cannot change the identifier once the subaccount has been created.
4. Click **Create Subaccount**

Via the API, use the [Subaccounts](/developer/transactional/api/subaccounts/add) endpoint. (For sample code, see [the subaccounts guide](/developer/transactional/guides/manage-different-users-subaccounts).)

Once your subaccount is up and running, you can use the `subaccount` parameter of the [`/messages/send`](/developer/transactional/api/messages/send) endpoint, or you can use the [`X-MC-Subaccount`](/developer/transactional/docs/smtp-integration#x-mc-subaccount) header if you’re sending via SMTP.

> **Note**
>
> **Note**: Make sure you enter the subaccount name correctly. If you try to send an email via the API from a subaccount that doesn’t exist, it will fail with an error. However, if you try to send from a nonexistent subaccount via SMTP, the email will be accepted by the SMTP server but will ultimately fail to send.

## View subaccount activity

Mailchimp automatically tracks subaccount activity. The easiest way to view it is directly in your account, and there are two ways to do so.

To see a high-level overview, navigate to [**Outbound Activity**](https://mandrillapp.com/activity), click the **Show All Options** toggle in the search panel, and choose your subaccount from the **Subaccounts** dropdown.

If you’d rather get a lower-level overview—where you can also change account status, add notes, and see stats that aren’t available on the **Outbound Activity** view—navigate to [**Subaccounts**](https://mandrillapp.com/subaccounts) and click on the subaccount ID or the **View Details** button.

![Subaccounts screenshot](https://images.ctfassets.net/cxsachrr7h0p/2UY00dt3qn8Zrrft6XYwfd/4ac23a11f510cf599c24581d85ad0c52/subaccounts.png)

If you need programmatic access to account activity, you can use the [`subaccounts/info`](/developer/transactional/api/subaccounts/info) endpoint in the Transactional API. For sample code, see the [Manage Different Users with Subaccounts](/developer/transactional/guides/manage-different-users-subaccounts) guide.

## Custom hourly quotas

By default, subaccounts have their own [hourly quota](/developer/transactional/docs/reputation-rejections#hourly-quota) that works just like the main account, but you can also create a custom fixed hourly quota for individual subaccounts. For sample code to create or update a custom quota, see the [subaccounts guide](/developer/transactional/guides/manage-different-users-subaccounts).

To manage custom quotas in the app:

1. Navigate to [**Subaccounts**](https://mandrillapp.com/subaccounts) and select **View Details** next to the subaccount you’d like to edit
2. Click **set custom quota**
3. Enter or modify the quota value (must be greater than 0) and click **Set Quota**

To remove a custom quota, navigate to the subaccount’s details and select **edit custom quota**. Then select **Switch to Automated Quota**, which will restore the subaccount to the default reputation formula.

> **Note**
>
> **Note**: Two hourly quotas are considered for each subaccount: the primary account’s quota and the subaccount’s quota. The quota for a subaccount can’t be set to a value that’s higher than the primary account’s hourly quota.
>
> However, if a subaccount sends a message that would put *either* the subaccount or the primary account over its hourly quota, the emails will be placed in the primary account’s backlog; subaccounts do not have separate backlogs.
>
> While exceeding a subaccount’s quota will place its new emails in the backlog, email from subaccounts that have not exceeded their quota will still send unless the primary account's quota has been exceeded.

## Subaccount rejections

If a message sent from a subaccount bounces, or if the recipient unsubscribes or reports a message as spam, their address will automatically be moved to that subaccount’s [Rejection Denylist](/developer/transactional/docs/reputation-rejections#rejected-emails). This will *only* affect that subaccount; other subaccounts will still be able to send to that recipient without issue.

To view the Rejection Denylist for a specific subaccount, navigate to [**Rejection Lists**](https://mandrillapp.com/settings/rejections) and select the subaccount ID from the **View Denylist For Subaccount** drop-down menu.

You can also retrieve the Rejection Denylist for a subaccount via the [Transactional API](/developer/transactional/api/rejects/list).

## Pause and resume sending

You can temporarily stop sending for any subaccount using the app or the Transactional API. While sending is paused, emails will be queued into the account’s backlog.

To pause sending for a subaccount, navigate to the [**Subaccounts**](https://mandrillapp.com/subaccounts) page, choose \*\*View Details \*\*on the specific subaccount, and click **Pause**. To resume sending, click **Resume**.

To walk through the code for pausing and resuming, see the [subaccounts guide](/developer/transactional/guides/manage-different-users-subaccounts).

## Delete a subaccount

Deleting a subaccount is permanent, and Mailchimp cannot recover a subaccount after it is deleted. This will not remove email activity associated with the subaccount, but you can no longer search activity by the subaccount name.

To delete a subaccount via the app, navigate to the [**Subaccounts**](https://mandrillapp.com/subaccounts) page and click the **Delete** button next to the subaccount you want to remove. With the API, you can use the [`subaccounts/delete`](/developer/transactional/api/subaccounts/delete) endpoint.