Every email marketer knows: if you want to accurately measure the effectiveness of a campaign, you need to add UTM tags to all your links.But doing this manually is tedious and time-consuming. In this article, we'll explain how to automate UTM tagging in emails using Letteros or other tools.

What are UTM tags?

UTM tags are special parameters added to a URL to:

  • track the traffic source,
  • see the campaign,
  • understand which link in the email performed best.

Example of a link with UTM tags:https://example.com/?utm_source=email&utm_medium=campaign&utm_campaign=april_promo

Why you shouldn't do it manually

❌ Slow: you have to check every single link.❌ Errors: it's easy to forget a tag or put it in the wrong place.❌ Inconsistent: forget just once, and your stats get thrown off.

Automation solves these problems.

How to automate UTM tags in Letteros

Step 1. Enable auto-tagging

In your project or specific campaign settings:

  • turn on "Automatically add UTM tags."

Step 2. Set up a template

In Letteros, you can set up a template like:

  • utm_source=email (channel),
  • utm_medium=newsletter (type),
  • utm_campaign={{campaign_name}} (campaign name).

Fields can be auto-filled from your campaign data.

Step 3. Apply to all links

The Letteros editor will add UTM tags to all external links in the email:

  • buttons,
  • text links,
  • images with clickable links.

If tags are already set manually somewhere, they won't be overwritten.

What to do if you're working outside Letteros

If you're using third-party platforms:

  • use a generator, such as ga-dev-tools,
  • add UTM tags through your ESP (many let you set up auto-tagging in the campaign settings),
  • or ask a developer to build a script at the email preparation stage.

Important tips

✔ Check that your links don't "break" because of UTM tags (especially if they lead to landing pages with parameters).✔ Don't duplicate UTM tags manually and automatically.✔ Use a consistent naming scheme (for example, always utm_source=email, not newsletter).

Conclusion

Automating UTM tags saves time, reduces errors, and makes your analytics transparent. In Letteros, you can turn it on in literally 1 minute and be confident that no link goes untracked.