Email Campaign Performance Metrics: What to Track

Email campaign performance metrics show what recipients actually do with your emails: open rates, click-through rates, conversions and more. They tell you what works and what does not.

Why Email Campaign Performance Metrics Matter

Sending campaigns without reading the numbers means guessing. Metrics are the feedback loop that shows whether the message lands.

With the data you stop paying for tactics that do not work and do more of what does. Each number points to a specific part of the campaign. A high click-through rate means the offer worked. A high bounce rate means the list needs cleaning.

The metrics depend on each other: an email that is not delivered cannot be opened, and one that is not opened cannot be clicked. Read them together.

An overview of the metrics covered below:

Connecting Metrics to ROI

The point of the metrics is to connect email to revenue. Email can return a lot per dollar spent: Backlinko's statistics roundup, citing Litmus, reports that brands that often use dynamic content get about $44 per $1 spent, against $36 for brands that rarely or never do (Backlinko).

Averages like these hide wide differences between companies. The only ROI that matters is the one you measure on your own campaigns, which is why tracking the metrics below is worth the effort.

After Delivery: Opens and Clicks

Delivery is only the first step. The next questions are whether the recipient opens the email and whether they click.

Engagement metrics give you the first read on your subject lines, your content and your sender name.

Open Rate

The Open Rate is the percentage of delivered emails that were opened. It reflects the subject line and whether people recognise and trust the sender name.

It is an imperfect metric. Opens are tracked with a tiny image. Apple Mail Privacy Protection downloads that content in the background whether or not the recipient reads the email (Apple), which inflates opens, while clients that block images undercount them. Use open rates to compare subject lines within one list. Opens do not prove that people read the email.

Open Rate = (Number of Unique Opens / Number of Emails Delivered) x 100

If the open rate is low, check deliverability and sender reputation first, then the subject lines; how to improve cold email open rates covers the checks in order. A/B test subject lines: a question against a statement, short against descriptive. For ideas, see these cold email templates.

Click-Through Rate

The Click-Through Rate (CTR) is the percentage of delivered emails in which a recipient clicked at least one link. It is one of the most useful email campaign performance metrics because it measures whether the content and the offer worked.

A high CTR means the message, the layout and the call-to-action (CTA) worked together, and that the email delivered on the subject line's promise.

CTR = (Number of Unique Clicks / Number of Emails Delivered) x 100

To raise CTR, use one clear CTA that is easy to find. Many competing links often mean fewer clicks overall. Use specific, action-oriented text, such as "Get the guide" instead of "Click here."

For reference, Campaign Monitor's benchmark of 2021 data (more than 100 billion emails) found an average open rate of 21.5% and an average click-through rate of 2.3% (Campaign Monitor). Industry, list type and email type all shift these numbers.

Audience and List Health

Good open and click rates are not enough. Long-term results depend on the health of your list. A neglected list leads to bounces, complaints and a damaged sender reputation.

List health metrics show whether you are keeping your audience or losing it, and protect your ability to reach the inbox.

Unsubscribe Rate

The Unsubscribe Rate is the percentage of recipients who unsubscribe after an email. It is useful feedback.

A sudden spike means something changed: the content missed, or you are sending too often.

Unsubscribe Rate = (Number of Unsubscribes / Number of Emails Delivered) x 100

Campaign Monitor's benchmark of 2021 data put the average unsubscribe rate at 0.1%. If yours climbs, find the emails that caused it and ask why.

Bounce Rate

The Bounce Rate is the percentage of emails that were rejected and never delivered. High bounce rates are a common sign of a bad list, and Postmaster Tools reports delivery errors.

There are two kinds of bounces:

• Hard bounces: Permanent failures. The address is fake, misspelled or no longer exists. Remove these immediately.

• Soft bounces: Temporary failures, such as a full mailbox or a server that is briefly down. Platforms retry them; if an address keeps soft-bouncing, remove it too.

A high hard-bounce rate looks like a purchased or outdated list. Verify addresses before you send; see our guide to email verification programs.

Spam Complaint Rate

The Spam Complaint Rate counts recipients who mark your email as spam. For your sender reputation, this is the most damaging signal: it tells the mailbox provider that the email is unwanted.

The thresholds are low. Google asks senders to keep the spam rate reported in Postmaster Tools below 0.1%, that is 1 complaint per 1,000 emails, and never to reach 0.3% (Google sender guidelines).

To keep it near zero, use double opt-in for new subscribers, make the unsubscribe link easy to find, and send what people signed up for. To check a message before it goes out, see spam test score.

From Clicks to Business Results

Opens and clicks measure interest. Leadership wants to know what email contributes to revenue. For that you follow the recipient past the click.

Conversion Rate

The Conversion Rate measures how many recipients completed the action the campaign was built for.

What counts as a conversion depends on the goal:

• A purchase in your store.

• A form fill for a lead magnet.

• A free-trial sign-up.

• A webinar registration.

It shows how well the email and the landing page work together.

Conversion Rate = (Number of People Who Completed the Desired Action / Number of Emails Delivered) x 100

A high CTR with a low conversion rate points to a disconnect: the landing page does not match the email's promise, or the form is too long. Look at the whole journey. For longer B2B cycles, plan the follow-ups: cold email follow-up sequence.

Revenue Per Email

If you sell online, tie email directly to revenue. The standard metric is Revenue Per Email (RPE): the average revenue each delivered email generates.

Divide the campaign's revenue by the number of emails delivered. A campaign delivered to 10,000 subscribers that brought in $5,000 has an RPE of $0.50.

RPE lets you compare campaigns by profit. Does a 20% discount beat free shipping? Which segment brings in the most revenue?

Email Campaign Types and Their Metrics

Different campaigns have different jobs, so judge them by different metrics.

A newsletter will not have the RPE of a Black Friday sale. Define success for each campaign type separately.

Personalization and Automation

Once the basics are in place, two things move the metrics further: personalization and automation.

Personalization

Personalization goes beyond {{first_name}}. It uses your data to show different content to different people in the same campaign: product recommendations based on last month's purchase, articles related to the pages someone visited.

Test it like anything else: send a personalized version against a generic one and compare clicks and conversions.

Automation

Automation sends the right message at the right time, triggered by what subscribers do, without manual work.

Common automated sequences:

• Welcome series: Greets new subscribers and sets expectations.

• Abandoned cart reminders: Reminds people who almost bought.

• Re-engagement campaigns: Tries to win back subscribers who stopped engaging.

Triggered emails arrive when the topic is on the recipient's mind, so they usually outperform one-off broadcasts. Track them as separate campaigns so you can see what each flow contributes.

FAQ: Email Metrics

How Do I Improve My Open Rate?

Compare against your own previous campaigns: privacy features inflate opens. For the checks in order and what to measure instead of opens, see how to improve cold email open rates.

How Do I Get More Clicks?

Start with something worth clicking: content that solves a problem or an offer people want.

Use one clear call-to-action with specific wording and a button that is easy to tap on a phone. Then test the text, placement and design.

The click is only half of it. The landing page has to deliver exactly what the email promised, or the click is wasted.

My Bounce Rate Is High. Why?

A high bounce rate almost always means an old or low-quality list, and it hurts the delivery of all your emails.

Separate the two types. Hard bounces are invalid addresses: remove them immediately. Soft bounces are temporary: if an address keeps soft-bouncing, remove it too.

Fix it at the source. Do not buy lists, use double opt-in, verify addresses before large sends, and remove contacts who stopped engaging.

Outreach2day sets up and maintains the sending infrastructure behind your campaigns, so you can focus on the message.