What Is Email Open Rate and How Do You Improve It?

Email open rate is the percentage of your email subscribers who open a given email campaign. It is one of the most widely tracked metrics in email marketing — and one of the most frequently misunderstood.

A low open rate suggests your subject lines aren’t compelling enough, your sending frequency is too high, or your list includes too many disengaged subscribers. But improving open rates requires understanding what drives them in the first place. This guide explains what open rate tells you and the most effective ways to improve it.

What Is a Good Email Open Rate for UK Businesses?

Open rate is calculated by dividing the number of unique opens by the number of emails successfully delivered, then multiplying by 100. If you send 1,000 emails, 50 bounce, and 200 of the 950 delivered are opened, your open rate is 21%.

However, open rate figures since 2021 should be interpreted with caution. Apple’s Mail Privacy Protection (MPP) feature, introduced on iOS 15, automatically preloads email content for Apple Mail users — which registers as an ‘open’ even if the person never actually read the email. This has inflated reported open rates for many businesses by 10–20 percentage points. A headline figure of 50–60% open rate today may reflect significant MPP inflation rather than genuine engagement.

That context aside, typical open rates vary significantly by industry. In the UK, B2B businesses and professional services tend to see open rates in the 20–35% range. E-commerce and retail typically see lower rates of 15–25%. Highly niche newsletters with deeply engaged audiences can see rates well above 40%. Compare your rates to industry benchmarks rather than cross-industry averages, and track your own trends over time rather than obsessing over absolute figures.

The Main Factors That Drive Open Rate

The subject line is the primary driver. A specific, curiosity-provoking, or useful subject line will dramatically outperform a generic one with the same audience. Test subject line formats — questions, numbered lists, provocative statements — and use A/B testing where available to understand what your specific subscribers respond to.

Sender name and from address also matter. Emails from a recognisable human name (‘James at Acme’) typically open better than those from an impersonal ‘Acme Ltd’ address — particularly for smaller businesses where the person behind the business is part of the brand. Make sure your from address is consistent and recognisable — changing it confuses subscribers and triggers spam filters.

List quality is a less visible but equally important factor. A list with a high proportion of disengaged or irrelevant subscribers will depress your open rate regardless of how good your subject lines are. Regular list cleaning — removing subscribers who haven’t opened any emails in six months or more — typically improves open rates noticeably.

Practical Steps to Improve Your Open Rate

Segment your list so you’re sending more relevant emails to subgroups within your audience. If you have subscribers in different industries, at different stages of the customer journey, or with different interests, sending them all the same email will underserve most of them. Even simple segmentation — new subscribers versus long-term subscribers, or customers versus prospects — can meaningfully improve open rates.

Review your sending frequency. If you’re emailing weekly and open rates are falling, try reducing to fortnightly and see whether engagement recovers. Equally, if you only email once a month, some subscribers may have forgotten who you are by the time your next email arrives. Find the frequency that maintains awareness without creating fatigue.

Run a re-engagement campaign for inactive subscribers before removing them. A short series of emails with a clear message — ‘We’ve noticed you haven’t opened our emails recently — are you still interested?’ — will recover some subscribers and give you a clean basis for removing those who don’t respond. At Xpose, we’ve helped Norwich and Norfolk businesses clean and re-engage their lists with consistently positive results on deliverability and engagement metrics.