How do I set up bounce handling for transactional email?

To set up bounce handling for transactional email, you generally need to:

1. Send mail through a provider that supports bounce notifications Examples: Amazon SES, SendGrid, Mailgun, Postmark, SparkPost.

2. Configure a Return-Path / envelope sender Bounces are usually sent to the envelope-from address, not the visible From: header.
   Set this to an address or domain you control, often something like:

   • bounce@yourdomain.com
   • or a provider-managed bounce domain

3. Receive bounce notifications There are two common ways:

   • Webhook/API notifications from your email provider
   • Inbound mailbox processing if you manage the bounce address yourself

4. Parse the bounce type Distinguish between:

   • Hard bounces: invalid address, rejected permanently
   • Soft bounces: mailbox full, temporary issue, retry later
   • Complaints: recipient marked as spam

5. Update your recipient database Automatically:

   • suppress hard-bounced addresses
   • retry soft bounces according to a policy
   • suppress complained addresses immediately

6. Use a unique identifier per message Add metadata so you can map a bounce back to the original recipient/message, such as:

   • custom headers
   • provider tags
   • message IDs stored in your DB

7. Set up monitoring and logging Track bounce rates and investigate spikes, which may indicate:

   • poor list quality
   • authentication issues (SPF/DKIM/DMARC)
   • spam filtering
   • sending reputation problems

Recommended setup pattern

For transactional email, the simplest robust pattern is:

• Use a provider like SES / SendGrid / Mailgun / Postmark
• Configure bounce webhooks
• Attach a message ID or recipient tag
• On bounce/complaint events, mark the recipient as suppressed
• Keep an audit log for troubleshooting

If you’re using Amazon SES

Typical setup is:

• verify domain
• set up SPF/DKIM
• configure SNS or Event Destinations for bounce/complaint notifications
• subscribe a webhook/Lambda/SQS consumer
• process events and suppress recipients

If you’re using SendGrid/Mailgun/Postmark

Usually:

• enable event webhooks
• listen for bounce, dropped, spamreport, deferred
• act on events in your app

If you want, I can give you:

• a provider-specific setup for SES, SendGrid, Mailgun, or Postmark
• a database schema for bounce tracking
• or example webhook code in Node.js/Python.