For years, the “Open Rate” was the golden metric of email marketing. You sent a newsletter, checked how many people opened it, and patted yourself on the back if the number was above 20%.

Then, Apple introduced Mail Privacy Protection (MPP) in iOS 15, and everything changed. MPP pre-loads images (including tracking pixels) on Apple’s proxy servers, making it look like an email was opened even if the user never saw it.

Suddenly, open rates became artificially inflated and completely unreliable. If you are still judging the success of your email campaigns by open rates, you are flying blind.

Clicks are the new currency of email marketing. Here is how to track them effectively and prove the true ROI of your email campaigns.

The Problem with Default ESP Tracking

Every major Email Service Provider (ESP) like Mailchimp, Klaviyo, or Hubspot offers built-in click tracking. When you add a link to your email, they automatically wrap it in their own tracking domain.

While this is convenient, it presents three major problems for serious marketers:

Ugly, Unbranded Links: When a user hovers over a link to your new product (yourstore.com/product), they see a massive, alphanumeric string like click.mailchimp.com/track/1a2b3c4d5e. This looks suspicious and can lower click-through rates.
Siloed Data: ESP analytics only tell you what happened inside the email. Once the user clicks through to your website, the ESP loses track of them.
Deliverability Risks: If your ESP shares a tracking domain pool with a spammer, your emails might get caught in spam filters, even if your sender reputation is pristine.

The Solution: Custom Domains + UTMs

To get an accurate, end-to-end picture of your email attribution, you need to combine custom branded links with strict UTM tagging.

Step 1: Set up a Custom Tracking Domain

Instead of relying on your ESP’s generic tracking links, use a dedicated link tracking platform like TrackFluenz to set up a custom subdomain (e.g., go.yourbrand.com).

When users hover over a link in your email, they see your brand name, reinforcing trust and increasing the likelihood of a click. Furthermore, because you own the domain, your deliverability isn’t impacted by bad actors on a shared ESP domain.

Step 2: Tag Everything with UTM Parameters

Every single link in your email should be tagged with UTM parameters. This is how you bridge the gap between the email click and the website conversion in Google Analytics.

Here is a standard framework for email UTMs:

utm_source=newsletter (or the specific name of your email list)
utm_medium=email (Always use “email” here, never “newsletter” or “eblast”)
utm_campaign=spring_sale_announcement (The specific campaign)
utm_content=hero_button (Use this to differentiate the main CTA button from a text link in the footer)

Step 3: Shorten and Track

Instead of pasting the massive UTM URL into your email builder, shorten it using your custom tracking domain.

The user clicks go.yourbrand.com/spring-sale. TrackFluenz logs the click data (geography, device, time), and instantly redirects them to your website, preserving the embedded UTM parameters so they flow seamlessly into your web analytics platform.

Connecting Clicks to Revenue

By moving beyond simple open rates and implementing a robust click-tracking strategy, you can finally answer the question your CEO is asking: “How much revenue did that newsletter actually generate?”

You’ll know exactly which links drove the most traffic, which CTAs converted the highest, and ultimately, the true ROI of your email marketing efforts.