# Set Up Resend

> Resend is a simple option for sending email through an API. To connect Resend, add an API key, verify your sending domain, and configure one webhook endpoint. Mailrith uses the webhook endpoint to update subscriber statuses automatically after bounce and complaint events.

- Human page: https://mailrith.com/docs/setup-resend
- Markdown page: https://mailrith.com/docs/setup-resend.md
- Category: Campaigns & Delivery
- Reading time: 7 min read
- Last updated: 2026-07-13
- Related keywords: Set Up Resend, Set Up Resend documentation, Campaigns & Delivery, Campaigns & Delivery documentation, Mailrith documentation, Mailrith help, Before You Start, Mailrith Fields, Resend Setup, Webhooks and Test Send, Email Delivery Connections, Broadcasts, Sequences

## AI Agent Notes
- Use this article as step-by-step Mailrith product guidance, not as legal, financial, or deliverability advice unless the article says so.
- Preserve exact Mailrith UI labels from the steps when explaining a workflow.
- Prefer Mailrith's product term Subscribers when referring to people on an email list.

## What this guide covers
Connect Resend with an API key and verified domain, then add the Mailrith webhook so bounce and complaint updates reach the correct Subscribers.

## Sections
- Before You Start
- Mailrith Fields
- Resend Setup
- Webhooks and Test Send

## Visual Reference
![Mailrith email delivery connections page showing connected services with action controls.](https://mailrith.com/docs/screenshots/email-delivery-connections.png)

The Email Delivery Connections page lists every connected service. From here you can add a connection, send a test email, view delivery-event links, and assign connections to workspaces.

## Before You Start

Resend connects to Mailrith with an API key and a verified sending domain. Before you create the connection, make sure you have:

- **A verified domain in Resend:** your From email's domain must be verified in Resend and ready to send.
- **A Resend API key:** the key Mailrith will use to send email through Resend.
- **A sender address:** the From email subscribers will see in their inboxes.
- **Webhook access:** access to Resend webhook settings so Resend can send bounce and complaint events back to Mailrith.

If your domain is still being verified, wait until Resend shows your domain as ready before you test the connection in Mailrith. An API key cannot send email successfully from a domain that Resend has not approved.

## Mailrith Fields

In Mailrith, click [Email Delivery Connections](https://mailrith.com/docs/email-delivery-connections.md) in the left sidebar, click **Create Connection**, choose **Resend** in **Select Email Delivery Service**, and complete these fields in **Connect Email Delivery Service**:

- **Connection name:** an internal label, such as "Resend Product Updates".
- **API Key:** the Resend key Mailrith uses for sending.
- **From name:** the sender name subscribers see.
- **From email:** an email address on a verified Resend domain.
- **Workspaces:** the Mailrith workspaces that can use this connection.

## Resend Setup

1. In Resend, verify the sending domain you plan to use for the From email.
2. Create a new Resend API key, or copy an existing active API key.
3. In [Email Delivery Connections](https://mailrith.com/docs/email-delivery-connections.md), click **Create Connection**, choose **Resend**, and paste the API key.
4. Enter the From name, From email, and workspace assignments for the connection.
5. Click **Save**, then use **Send Test Email** from the connection row to confirm Mailrith can send through Resend.

If the test fails, confirm that Resend shows your domain as verified, the API key is active, and the From email uses that verified domain.

## Webhooks and Test Send

Resend can send bounce and complaint events to Mailrith through one webhook URL.

1. In Mailrith, click **Email Delivery Connections**, click **Webhooks** on the Resend connection, and copy the delivery-event webhook URL for that connection.
2. In Resend, open the webhook settings.
3. Add the Mailrith URL as the webhook endpoint.
4. Enable bounced and complained email events so Resend sends both event types to Mailrith.
5. Save the webhook, then monitor webhook deliveries after test or live sends and confirm Resend reports successful deliveries to the Mailrith endpoint.

Delivery-event webhooks let Mailrith update subscriber statuses after Resend reports a bounce or complaint. Without these webhooks, subscribers who bounced or complained may stay active until you update their statuses another way.

## Related Guides
- [Email Delivery Connections](https://mailrith.com/docs/email-delivery-connections.md): You connect your own email delivery service. Mailrith then manages subscribers, campaigns, follow-up, and reports while that service sends the emails.
- [Broadcasts](https://mailrith.com/docs/broadcasts.md): Use broadcasts for newsletters, product launches, announcements, and any message you send once to selected subscribers. Compose, target, test, and send or schedule the campaign in one workflow.
- [Sequences](https://mailrith.com/docs/sequences.md): Sequences send a series of emails over time as subscribers move through the steps. Use sequences for onboarding, nurture campaigns, and educational content that should be sent over days or weeks.