Email Open Rate: What Is Good and How to Improve Yours

Open rate is the most observed metric in email marketing — and one of the most misunderstood. An isolated number means nothing: a 25% open rate is excellent for an e-commerce with a list of 50,000 contacts and mediocre for a niche B2B list with 800 highly segmented subscribers. Context is everything.

This guide explains what open rate is, how to interpret your number in the right context, real benchmarks by segment, and the subject line and pre-header techniques that make a practical difference in the open rate of your next campaign.

What Is Open Rate and How Is It Calculated

Open rate = (emails opened ÷ emails delivered) × 100. For example: 500 opens out of 2,000 emails delivered = 25% open rate.

Attention to the technical limitation: since September 2021, Apple’s iOS 15 introduced Mail Privacy Protection (MPP) — which pre-loads tracking pixels on Apple devices, artificially inflating the open rates reported by tools like Mailchimp and ActiveCampaign. This means that some of the “opens” you see in the report may be automatic triggers from the Apple system, not actual reads. Click-through rate (CTR) has become the most reliable metric for real engagement after this change.

Benchmarks By Segment (Brazil 2026)

Comparing your open rate with the overall market average is not very useful — the variation by segment is huge. Use the benchmarks below as a reference for your industry:

• Education / Online Courses: 28–35%
• Professional Services (accounting, law, consulting): 25–32%
• Digital Marketing / Agencies: 22–28%
• Health and Wellness: 24–30%
• E-commerce (retail): 18–22%
• SaaS / Technology: 20–26%
• Finance / Insurance: 20–25%
• Restaurants / Food: 18–24%

If your rate is consistently below the benchmark for your segment, there is a relevance issue (wrong content for the audience), frequency issue (too many emails causing fatigue), or list quality issue (disengaged contacts).

Subject Line: The Factor With the Greatest Impact on Opens

The subject of the email (subject line) is responsible for 60% to 70% of the decision to open or not. The recipient sees three elements before opening: sender, subject, and pre-header (preview text). If any of these do not motivate the opening, the email is not read — regardless of the quality of the internal content.

Subject Line Techniques That Work

• Curiosity with information gap: “The mistake 80% of companies make on Instagram” — the reader opens to find out if they are making the mistake. It works, but it must be honored by the content — clickbait destroys trust.
• Numerical specificity: “7 subject line techniques tested on 50,000 emails” is more clickable than “Subject line tips.” Specific numbers convey credibility.
• Personalization with name: “[Name], your May report is ready” — personalization in the subject increases opens by an average of 26% according to HubSpot data. Not all tools offer this easily, but when available, use it.
• Real urgency: “Last 24 hours: sign up for the webinar” — urgency works when it is genuine. False urgency (“Offer expires now!” in an email sent every week) trains the reader to ignore.
• Direct question: “Do you know how much an inactive customer costs?” — questions that touch on a known pain point for the reader have a high open rate in B2B lists.
• Short subject (less than 40 characters): short subjects perform better on mobile, where over 60% of emails are opened. Example: “New guide available” or “About your SEO strategy.”

What to Avoid in the Subject Line

• Words that trigger spam filters: “Free,” “Promotion,” “Win,” “Click here,” “100%” in all caps
• Excessive capital letters: “UNMISSABLE OFFER” goes to spam or junk
• Excessive punctuation: “!!!”, “???” reduce credibility
• Very long subjects: over 60 characters are cut off in most mobile email clients
• Deceiving about the content: a subject that promises X and delivers Y destroys trust and increases unsubscribes

Pre-Header: The Ignored Complement

The pre-header (preview text) is the visible text in the inbox after the subject — and it is ignored by most companies. When not manually set, tools display the beginning of the email (often “If you cannot view this email, click here” — terrible).

The pre-header should complement the subject, not repeat it. If the subject is “7 subject line techniques tested,” the pre-header could be “None of them use emojis — and the data proves why.” Together, they create enough curiosity for the opening.

Other Factors That Affect Open Rate

Sender Name

Emails from a person (“Felipe from Focofy”) have a consistently higher open rate than emails from a company (“Focofy Marketing”). The reader opens emails from someone they know. For newsletters and content communications, using a personal name + company (“Felipe | Focofy”) is the best balance.

Time and Day of Sending

The best times vary by audience — use your own Insights data before following generic averages. That said, benchmarks from the Brazilian market indicate:

• B2B: Tuesday to Thursday, between 9 AM and 11 AM or 2 PM and 4 PM
• B2C: Tuesday to Thursday, between 7 PM and 9 PM; Saturday morning for e-commerce
• Avoid: Monday morning (inbox full from the weekend), Friday afternoon (mentally already in the weekend), Sunday

List Segmentation

Sending the same email to the entire list is the most common cause of low open rates. Segmenting by interest, behavior (who opened the last 3 emails vs. who hasn’t opened any), or funnel stage can double the open rate of the relevant segment.

How to Test and Improve: A/B Testing

The most reliable way to improve open rate is to systematically test. Most tools (Mailchimp, ActiveCampaign, RD Station) offer A/B testing for subject lines: you send two different subjects to two samples of the list and the winner is automatically sent to the rest.

Rules for reliable A/B testing: test only one variable at a time (subject A vs. subject B, not subject + different times), use samples of at least 200 contacts per variant, and wait for significant results before declaring a winner. A 2% difference may be statistical noise with small samples.

Conclusion

Open rate is a key performance indicator that reflects the health of the relationship with your list — but it needs to be interpreted in context. Compare with benchmarks from your segment, monitor the trend over time, and use A/B testing to optimize the controllable factors: subject, pre-header, sender, and timing.

The ideal open rate is one that, combined with a healthy click rate, generates the business results you need. Also see how to automate email flows to maintain engagement in sequences beyond the single send, and check out the complete Email Marketing hub.