> For the complete documentation index, see [llms.txt](https://docs.mailtrap.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mailtrap.io/guides/integrations/vercel.md).

# Vercel

Step-by-step guide on how to integrate Mailtrap with your application hosted on Vercel to enable email sending capabilities.

Mailtrap’s native integration with Vercel removes manual setup friction, minimizes configuration mistakes, and makes it easy to follow a reliable testing-to-production email workflow.

This integration automatically configures the environment variables necessary for both testing (Sandbox) and production sending in your Vercel projects.

{% hint style="info" %}
The integration adds a set of three variables (`API_KEY`, `USE_SANDBOX`, and `INBOX_ID`) for each of the three Vercel environments: **Development**, **Preview**, and **Production**.
{% endhint %}

#### Prerequisites

* **Admin rights** for your Mailtrap account.
* A [verified sending domain](https://docs.mailtrap.io/email-api-smtp/setup/sending-domain) set up within Mailtrap.
* An existing **Vercel account** with one or more projects.

### Step-by-step integration guide

{% stepper %}
{% step %}

#### Initiate the integration

* Log in to your Mailtrap account
* Navigate to the [**Integrations** page](https://mailtrap.io/api-smtp/integrations) from the sidebar.
* Locate the **Vercel** card under the **AI & Development** section.
* Click the **Integrate** button.

<figure><img src="https://365478608-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgkNigAKiqQtQub1GOdjY%2Fuploads%2FhlvHtPQkqMk70wTXIbva%2Fvercel%201.png?alt=media&amp;token=4f9ac4f7-1fda-457b-8938-874bb871d59b" alt=""><figcaption></figcaption></figure>
{% endstep %}

{% step %}

#### Authorize with Vercel account

Click the **Authorize with Vercel** account button. You will be redirected to the Mailtrap listing page.

<figure><img src="https://365478608-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgkNigAKiqQtQub1GOdjY%2Fuploads%2FZlDLXoaqCo0RAPDYfjjv%2Fvercel%202.png?alt=media&amp;token=8224dd68-6261-409f-a7e7-3ce6c5367550" alt=""><figcaption></figcaption></figure>
{% endstep %}

{% step %}

#### Connect your Mailtrap account

On the Vercel integration page, click on **Connect Account** and then:

* Select your Vercel team.
* Select the specific project you want the integration to apply to.
  * **Note**: You’ll need to choose the project again on the Mailtrap side in the next step.
* Click **Connect Account** to proceed, and a new popup will appear.

<figure><img src="https://365478608-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgkNigAKiqQtQub1GOdjY%2Fuploads%2FJthlJgavjqgy4v4yB58J%2Fvercel%204.png?alt=media&amp;token=bed41d69-da6d-47c0-a60b-69ec97cc247c" alt=""><figcaption></figcaption></figure>

{% hint style="warning" %}
Currently, the integration cannot be added to all projects, only to specific ones.
{% endhint %}
{% endstep %}

{% step %}

#### Select a Vercel project in Mailtrap

Select the specific Vercel project you want to configure from the dropdown menu.

<figure><img src="https://365478608-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgkNigAKiqQtQub1GOdjY%2Fuploads%2FPM3eIM8Fi8pjWpVh0Khq%2Fvercel%205.png?alt=media&amp;token=efe73142-54a7-4c79-8168-0422cd61fd84" alt=""><figcaption></figcaption></figure>
{% endstep %}

{% step %}

#### Create an API Token

Choose the domain from which you intend to send emails and click **Create Token**. The token will be generated at the domain level.

<figure><img src="https://365478608-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgkNigAKiqQtQub1GOdjY%2Fuploads%2FzukqKxnVpT7sBl7hJ8IM%2Fvercel%206.png?alt=media&amp;token=b1688902-8de0-4e47-9713-89c0655497c0" alt=""><figcaption></figcaption></figure>
{% endstep %}

{% step %}

#### Add environment variables and complete the installation

The following variables will be added to your Vercel project:

* `MAILTRAP_API_KEY` – Required for both testing and sending.
* `MAILTRAP_USE_SANDBOX` – Set to **True** to use Mailtrap's Sandbox for testing, or **False** for production sending.
* `MAILTRAP_INBOX_ID` – Required if using the Sandbox. Select the desired Inbox from the dropdown.

Once you’re done reviewing the variables, click **Set Environment Variables**. This will finalize the integration and close the setup window.

<figure><img src="https://365478608-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgkNigAKiqQtQub1GOdjY%2Fuploads%2FRZdyqkRZOdiOHs4K4iVa%2Fvercel%207.png?alt=media&amp;token=44e03138-c66e-4719-b4ee-221ddc0071fa" alt=""><figcaption></figcaption></figure>

#### Verifying the integration in Vercel

Once the setup is complete, you can verify the environment variables in your Vercel account:

1. Go to your Vercel project settings.
2. Navigate to the **Environment Variables** section.
3. You should see nine Mailtrap environment variables. A set of three variables (`API_KEY`, `USE_SANDBOX`, and `INBOX_ID`) for each of the three Vercel environments: **Development**, **Preview**, and **Production**.

<figure><img src="https://365478608-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FgkNigAKiqQtQub1GOdjY%2Fuploads%2FnHtxYFn0yAs9hcLAQk9K%2Fvercel%208.png?alt=media&amp;token=6e11354f-6ec6-4312-89c0-0bd30dcd9e95" alt=""><figcaption></figcaption></figure>
{% endstep %}
{% endstepper %}


---

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