Developers & API

How to Send Transactional Emails

Transactional emails — receipts, password resets, notifications — are mission-critical. OutSends separates transactional from marketing traffic, ensuring high-priority emails always get through.

Time: 15 min
Level: Advanced
transactional email api notifications automation

What you'll need

Before you start, make sure you have the following ready.

  • An OutSends account
  • A transactional email template
  • Your API key from OutSends

Step-by-step guide

Follow these steps to complete the setup.

Create transactional templates

Design your transactional email templates in OutSends. Keep them clean, responsive, and focused on the action.

Get your API key

Go to Settings > API. Generate an API key with "Transactional Send" permissions.

Send via REST API

Use POST /api/send/transactional with recipient, template ID, and personalization data.

Handle delivery events

Set up webhooks for transactional delivery events. Track opens, clicks, and bounces per message.

Monitor transactional performance

Use OutSends transactional dashboard to track delivery rates, response times, and error logs.

Tips for best results

Pro tips to get the most out of this setup.

  • Use separate API keys for transactional vs. marketing sending
  • Transactional emails should contain no marketing content — ISPs classify them differently
  • Set up a dedicated sending domain for transactional traffic

Frequently asked questions

What is the difference between transactional and marketing emails?

Transactional emails are triggered by user actions (purchase, signup) and are expected. Marketing emails are promotional.

Do transactional emails need unsubscribe links?

No, CAN-SPAM exempts transactional emails from unsubscribe requirements. But include a preference center link.

What is a good transactional delivery rate?

97%+ is expected. If below 95%, investigate authentication or content issues.

Related guides

Explore more how-to guides for OutSends.

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