Playbook

How to Increase Email Open Rates

Proven tactics to get more of your subscribers actually opening your emails.

This is part of the Supercharged Email playbook, built to help you get better results without guesswork.

TL;DR

Subject lines move opens more than anything else, test 2–3 per send.
Preview text is your second subject line. Don't leave it empty.
Send Tuesday or Thursday morning unless you have data saying otherwise.
Clean your list every quarter. Cold subscribers drag the whole list down.
Use a real human "From" name. "Jane at Brand" beats "Brand" almost every time.

1. Write Better Subject Lines

Keep subject lines under 50 characters for mobile
Use curiosity, urgency, or specificity
Personalize with the subscriber's name when possible
A/B test subject lines on every send
Try our subject line tool

2. Optimize Send Times

Tuesday, Wednesday, and Thursday tend to perform best
Test morning (9-10am) vs. afternoon (1-2pm) sends
Consider your audience's time zone
Use send-time optimization if your platform supports it

3. Clean Your List Regularly

Remove subscribers who haven't opened in 90+ days
Send a re-engagement campaign first
A smaller, engaged list outperforms a large, cold list
Monitor bounce rates and remove invalid addresses

4. Nail Your Preview Text

Preview text is the "second subject line", don't waste it
Complement (don't repeat) your subject line
Keep it under 90 characters
Preview with our Email Preview Tool

5. Build Sender Reputation

Use a consistent "From" name subscribers recognize
Authenticate your domain (SPF, DKIM, DMARC)
Avoid spam trigger words, use our Spam Score Checker
Send consistently to build inbox trust

Do this today

Score your next subject line with the Subject Line Tester
Write preview text that doesn't repeat the subject
Switch your From name to a real person's name
Run a re-engagement campaign on 60+ day inactives
Pick one send day and stick to it for 4 weeks

Frequently asked

Are open rates still trustworthy after Apple Mail Privacy?+

Roughly inflated by 30–50% for Apple-heavy lists. Use opens as a directional metric, not an absolute one. Click rate and replies are more honest.

What's a realistic open rate?+

20–25% for most lists, 30–40% for engaged niche lists, 40%+ for high-trust newsletters. Anything under 15% suggests a deliverability or list-quality issue.

Should I use emojis in subject lines?+

Test it. Emojis can boost opens 5–10% in lifestyle/retail niches but hurt opens in B2B and finance. Run the same email both ways before deciding.

What if my opens are dropping over time?+

Usually one of three things: list fatigue (you're sending too often), list rot (too many inactive subscribers), or content drift (you stopped delivering value). Audit in that order.

Do longer or shorter subject lines win?+

Short (under 50 chars) wins most of the time because mobile inboxes truncate. Long subject lines work when they're genuinely intriguing.

Put these strategies into action

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Related tools: Subject Line Tester · Email Preview · Send Time Optimizer
Playbooks: Email Frequency · Avoid the Spam Folder · A/B Testing