Email marketing conversion rates: what the numbers actually mean for small businesses

Most email marketing advice is written by the companies selling email marketing software. That creates an obvious problem: the benchmarks they publish tend to be best-case numbers, drawn from their top-performing customers, presented in a way that makes their product look essential.

So when MailerLite published a study analyzing over 300 million emails for actual conversion rate data, it is one of the more genuinely useful studies we’ve come across. It is based on e-commerce accounts with purchase tracking turned on, which means the numbers reflect real sales, not clicks or opens. Here is what the data found, and what it actually means for a small business with a few hundred or a few thousand subscribers.

Contents

• What the research found
• What this baseline actually means for you
• What are the wider email engagement benchmarks?
• What is the most important number in the study?
• Why is automation volume a trap?
• What are two quick wins worth acting on?
• How often to check what
• TL;DR

What the research found

The study covered 300,000+ campaigns and 10,000+ automations, all from accounts with a connected e-commerce store and purchase tracking enabled. An order was counted when someone clicked a link in an email and then bought within 30 days.

The headline numbers are modest but meaningful, and the third number is worth pausing on. Automated emails convert at a higher rate, but campaigns still drive the overwhelming majority of actual orders - meaning volume wins.

What this baseline actually means for you

If your email list has 500 subscribers and you send a campaign to all of them, you can expect roughly 1 to 2 sales from that single send. That is not a failure, the data shows that this is normal.

The problem is that most small businesses have no baseline to compare against, so they either assume their emails are working fine without checking, or they assume a low number of sales means something is badly wrong. Neither helps you improve - so start using the data to learn what performs best.

The more useful question is not “are you above or below 0.32%?” but “what happens to your conversion rate when you change something?” Once you know your own baseline, you can start running small experiments. Send to a narrower segment. Try a different subject line. Change how many links are in the email. The benchmark gives you a starting point, not a finish line. (As an aside - when it comes to the number of links/ctas in an email; less is more!)

One thing the study does not cover is the compounding effect. If you send twice a week, a 0.32% conversion rate on a 500-person list gives you roughly 16 sales per month from email alone. That is a solid revenue contribution for a small business, from a channel that costs almost nothing to run once the list is built.

What are the wider email engagement benchmarks?

Conversion rate is the metric that connects directly to revenue, but it does not tell you where a problem lives. If your conversion rate is below benchmark, the issue could be in your subject line (affecting who opens), your body copy (affecting who clicks), or your landing page (affecting who buys). Understanding the wider set of benchmarks helps you diagnose which part of the funnel is underperforming.

MailerLite’s 2025 data puts the median figures across all industries at:

Use these as rough orientation, not hard targets. Open rate in particular is distorted by Apple Mail Privacy Protection (see the note below), so treat it as directional rather than precise. Click-through rate and click-to-open rate are more reliable because they require genuine interaction by a human.

If your CTR is significantly below 2%, the problem is likely in the email itself: an unclear offer, too many competing links/buttons, or a weak call to action. If your CTOR is low but CTR looks reasonable, your subject line may be attracting the wrong readers. If both engagement metrics look fine but conversion is low, the issue is probably on the landing page, not in the email.

What is the most important number in the study?

The benchmark that changes how you should think about email strategy is the one that gets the least attention. Conversion rate doesn’t stay flat as your list size changes, it actually drops sharply the more people you send to.

A targeted send to under 500 people converts at more than ten times the rate of a send to your full list. See the link below to our email segmentation guide to understand how your business can benefit from a more targeted email audience.

The practical implication is that if you have a list of 2,000 people and you send every offer to all 2,000, you are leaving significant conversion rate on the table. Splitting that list by product interest, purchase history, or engagement level and sending each group something relevant will lift your numbers considerably.

This is not complicated to set up, as most email tools let you create segments based on tags, groups, or purchase behaviour. If you want a practical framework for doing this, the email segmentation guide covers the approach in detail. For a worked example of how segmentation and list hygiene lifted newsletter performance for a small retailer, see the online retail case study.

Why is automation volume a trap?

According to the study, automated emails convert at 0.42%, which is 31% better than the 0.32% campaign average. The reason is actually straightforward, as automations fire when someone does something that signals buying intent. An abandoned cart email goes out when someone was seconds from purchasing. A welcome sequence lands when someone is most engaged with you - the timing is inherently better for these automated emails that are being sent based upon a recipient’s action.

But this is a bit of a trap. Because automations convert better per email sent, it is tempting to conclude they are more important than regular campaigns, however the data shows the opposite. Campaigns generate roughly 92% of all email-driven orders, because the volume of emails sent through campaigns is far higher.

The right mental model is that automations are a floor and campaigns are the ceiling. A good abandoned cart sequence recovers sales you would otherwise lose. A weekly or fortnightly campaign to your whole list, or relevant segments of it, is where the majority of your email revenue actually comes from.

If you are not sending regular campaigns because building them feels like too much work, the honest answer is that you are leaving most of your email revenue potential unused. The email newsletter guide covers what actually makes campaigns worth opening, which is the real bottleneck once you commit to sending consistently.

For small online retailers specifically, the email marketing guide for small retailers covers the four automated sequences that drive most e-commerce email revenue and how to prioritise building them.

What are two quick wins worth acting on?

Beyond segmentation, the study surfaces two findings that are easy to act on immediately.

1. Keep your links to between two and five. Emails with two to five links converted at 0.56%, which is more than double the overall average. Emails with one link or more than five links performed significantly worse. The likely reason is focus: emails with two to five links tend to be built around a single offer or a small, coherent set of products. At the other end of the spectrum, emails with ten links are unfocused, while emails with only one link often feel sparse or transactional.

2. Add one targeted automation if you have none. You don’t need a complex sequence; the highest-return automations are usually the simple ones: an abandoned cart reminder, a welcome email with a first-order discount, or a follow-up to anyone who clicked a product link without buying. Each fires at a moment of demonstrated interest, which is exactly why automation conversion rates run higher than campaigns.

If your email tool is connected to your shop, these automations typically take less than an hour to configure. The conversion uplift they deliver runs indefinitely with no ongoing effort.

3 - Bonus tip: Watch your spam complaint rate. MailerLite’s data flags 0.3% as the threshold to stay below. Above that, inbox providers start treating your domain as a spam source, which reduces deliverability across your entire list, not just with the complainants. If you are above 0.3%, the fastest fix is a re-permission campaign or a hard prune of subscribers who have not engaged in the last six months.

Remember - sending less to a cleaner list consistently outperforms sending everything to everyone!

How often to check what

The numbers above are only useful if you actually look at them on a consistent basis. A simple review routine takes less than ten minutes a week and prevents the common pattern of only checking email stats when something feels wrong.

After each send, check deliverability by reviewing: delivery rate, bounce rate, and spam complaint rate. These need attention immediately if they move in the wrong direction. Once a week, review list growth: net new subscribers, unsubscribes, and which sources are adding the most contacts. Once a month, compare campaign conversion rates over time to spot trends. Data from a single campaign result isn’t always conclusive - a pattern across four or five campaign sends is a signal.

If you are using MailerLite, the custom reports feature lets you build a dashboard that surfaces these on a single screen. If you are on a different platform that doesn’t offer trend tracking, a simple spreadsheet with one row per campaign works just as well for small lists - we have even seen some of our clients feed their Marketing analytics into Claude or ChatGPT to spot trends in the data!

TL;DR

• The average email marketing conversion rate is 0.32% for campaigns and 0.42% for automated emails, based on a study of 300 million+ emails by MailerLite
• That translates to roughly 1 to 2 sales per 500 subscribers per send, which is a real revenue contribution at consistent sending frequency
• Campaigns drive 92% of total email orders because volume matters, even though automations convert at a higher per-email rate
• Targeted sends to fewer than 500 people convert at 3.28%, compared to 0.32% for a full-list send. Segmentation is the biggest lever available to most small businesses
• Emails with two to five links convert at double the average rate
• Keep your spam complaint rate below 0.3%. Above that, deliverability suffers for your whole list, not just with the complainants
• Your own baseline is more useful than any benchmark when trying to make improvements - ensure you know your campaign stats, then test how certain changes effect these stats