Open Rate explained: what's a good open rate and how to improve yours
Open rate is the percentage of recipients who open your email. Learn what a good open rate is, how Apple MPP affects your numbers, and practical tactics to improve it.
Open rate is the percentage of email recipients who open a given email, calculated as the number of opens divided by the number of delivered emails multiplied by 100.
It’s the most cited metric in email marketing — and simultaneously one of the most misunderstood.
What is a good open rate?
The cross-industry average sits at 20-25%, but variation is significant:
- B2B/SaaS: 15-22%
- E-commerce: 15-20%
- Nonprofits: 25-30%
- Niche newsletters: 35-50%
Small, engaged lists typically have higher open rates than large, broad ones. A list of 500 dedicated subscribers can easily exceed 40%, while a list of 50,000 rarely breaks 20%.
How open rate is measured
Email clients track opens via an invisible tracking pixel (a 1x1 image) that loads when the recipient’s email client renders the HTML email. When the image is fetched from the server, an open is registered.
This means opens are not registered if the recipient’s client blocks images by default — which many do.
Apple Mail Privacy Protection changed everything
In September 2021, Apple launched Mail Privacy Protection (MPP). The feature pre-loads all tracking pixels for Apple Mail users, regardless of whether they actually open the email.
The result: Apple Mail users always count as “opened.” Since Apple Mail accounts for 50-60% of all email clients, your reported open rate is likely 10-15 percentage points higher than reality.
This makes open rate less reliable as an absolute number. But it’s still useful for relative comparisons — such as A/B testing subject lines, where both variants are equally affected.
What affects open rate?
Four factors drive open rate:
- Subject line — it’s your headline. Short, specific subject lines with a clear benefit perform best. Avoid clickbait.
- Sender name — recognition is everything. Emails from a personal name (“Mikkel from Hermod”) get opened more often than from a company name alone.
- Timing — Tuesday through Thursday between 9-11 AM generally performs best for B2B, but test with your own list.
- Deliverability — emails that land in spam don’t count. Ensure correct SPF, DKIM, and DMARC setup.
How to improve your open rate
Start with the subject line. A/B test systematically: send two variants to 20% of your list, and let the winner go to the rest. Over time, you build knowledge about what your specific audience responds to.
Clean your list regularly, following Google’s sender guidelines for maintaining good deliverability. Remove contacts who haven’t engaged in 90+ days. A smaller, engaged list delivers better open rates — and better deliverability — than a large, passive one.
Always combine open rate with click-through rate (CTR) to get the full picture. A high open rate with low CTR means your subject line works, but the content disappoints. Read more in our guide to newsletters that actually get read.