What are custom tracking domains and why use them?

Custom tracking domains replace the ESP's default tracking domain with your own branded subdomain. Instead of links going through track.esp.com, they go through click.yourbrand.com.

Setup process:

1. Choose a subdomain (click.yourbrand.com, track.yourbrand.com, go.yourbrand.com)

2. Add a CNAME record in DNS pointing to your ESP's tracking server

3. Configure the ESP to use your custom domain

4. If using HTTPS (recommended), set up SSL certificate (many ESPs handle this automatically)

Benefits:

Reputation isolation: Your tracking domain's reputation depends only on your sending, not other ESP customers

Brand trust: Recipients see your domain when hovering over links, which looks more legitimate than third-party domains

Blocklist protection: If the ESP's shared tracking domain gets blocklisted, your custom domain remains unaffected

Security filter compatibility: Some filters treat unknown tracking domains suspiciously; your established domain may be treated better

Considerations:

Requires DNS access and configuration

SSL certificates need management (often automated)

If your sending damages the domain's reputation, you can't blame shared neighbors

It's painting your company name on the channel buoys. Traffic flows through your branded infrastructure.