Follow the path of an email
An email has to pass through several stages before it does any good: it must be delivered, noticed, opened, clicked and acted on. Each stage has measures, and a problem at an early stage limits everything after it. Looking at the whole path stops you from, say, rewriting a message that never reached the inbox.
Most email platforms report these measures in their dashboards. Definitions differ between platforms, so check each one’s current documentation.
Delivery and deliverability
Delivery rate is usually the share of sent messages that the receiving mail servers accepted. It is not the same as inbox placement. A message can be accepted and still land in a spam or promotions folder, which most platforms cannot fully see. This wider question is covered by email deliverability.
Things to watch:
- Bounces. Messages that could not be delivered. Hard bounces, for addresses that do not exist, should be removed promptly, while soft bounces are temporary. See the difference in how email bounces work.
- Spam complaints. When recipients mark a message as spam, mailbox providers take note. Even a small share can harm your sender reputation.
- Authentication. Setting up email authentication correctly helps providers trust your messages.
A rise in bounces or complaints is a warning sign, and good list hygiene helps prevent it.
Opens: why the number is less reliable
The open rate is usually estimated by loading a tiny hidden image in the email. This method has weaknesses:
- Some email apps and privacy features load images automatically, which can record an open even when the person never read the message.
- Some people block images, so real opens may go uncounted.
- Different clients behave differently, and these behaviours change over time.
As a result, open rates can be inflated, understated or simply inconsistent. They are still of some use for rough comparison between your own sends, particularly if you compare like with like over time, but they should not be your main success measure. Be especially careful when judging subject line testing by opens alone; clicks or conversions are usually more dependable evidence.
Clicks
Click rate (clicks divided by delivered emails) and click-to-open rate (clicks divided by opens) show whether the content prompted action. Click rate is generally the more trustworthy of the two, since it relies on a deliberate human action, though automated link scanners used by some security systems can generate false clicks.
Consider tracking which links get clicked. This shows which offers, topics or placements appeal to your readers. A clear call to action usually makes the intended click easier to measure and to earn.
Conversions and revenue
What happens after the click matters most. Depending on your goal, this might be a purchase, a booking, a download or a form completion.
- Conversion rate. The share of recipients, or of clickers, who completed the goal.
- Revenue or leads per email sent. Divides the outcome by the number of messages, which helps compare campaigns of different sizes.
- Attribution. Tag your links consistently so your analytics tool can attribute visits to the email. Remember that someone may read an email, then buy later through another route. This is a limit on any return on investment calculation.
Unsubscribes and list health
- Unsubscribe rate. The share of recipients who opt out after a send. Some unsubscribes are healthy, since people who do not want your emails are better off leaving. A sudden jump suggests a mismatch in content, frequency or targeting.
- List growth. New subscribers minus unsubscribes, bounces and removals.
- Engagement over time. Whether subscribers keep clicking or fade away. Inactive subscribers can be addressed with a win-back campaign or, eventually, removed.
Make unsubscribing simple. A visible, working unsubscribe link protects your reputation and is often a legal requirement, though rules vary by country and change over time.
Putting it into a simple report
A compact report per campaign might include:
| Stage | Measure |
|---|---|
| Delivery | Delivery rate, bounces, complaints |
| Attention | Opens (treated as a rough guide) |
| Action | Click rate, top-clicked links |
| Result | Conversions, revenue or leads |
| List | Unsubscribes, net list growth |
Review these over several sends, not one. A single campaign can be unusual because of timing, topic or a holiday.
Fair comparisons
- Compare similar emails. A newsletter, a promotion and an automated welcome series behave differently. Automated messages triggered by someone’s action, like a welcome series, often outperform broadcasts because they arrive at a relevant moment.
- Watch audience differences. Results for engaged customers will differ from those for cold subscribers. Customer segmentation helps you compare groups fairly.
- Beware small lists. On a small list, a few people can shift a percentage noticeably. Use caution before drawing conclusions from small differences, and consider whether the gap could be chance.
- Test one change at a time. An A/B test comparing two versions is a cleaner way to learn what helps.
- Avoid benchmark chasing. Industry averages vary widely and are measured in different ways. Your own history is usually the better yardstick.
Privacy and consent
Email marketing depends on permission. Rules on consent, record-keeping, and tracking within emails vary by country and change over time. See the basics of consent for email and SMS marketing, and check the rules that apply to you. This article is general information, not legal advice.
Used together, these measures show where an email programme is healthy and where it is leaking. Treat any single number, and especially the open rate, as one clue among several rather than a verdict.