64% of people open on the subject line, 45% on the sender name. What to put in each, why old spam-word advice is dead, and the 30-second preview-text win almost nobody takes.
Cyril Nie
Author
People decide to open an email based on two things: who it’s from, and what the subject says. 64% open based on the subject line. 45% open based on the sender name. Get both right.
“George from Acme” beats “Acme” by 5–15% in open rates. Use a real person’s name, not a department. Pick one and stay consistent — changing it confuses subscribers and can trip spam filters. Because the from-name appears on every email you ever send, it’s one of the highest-value things you can test.
Keep it under 30 characters. Phones cut off the rest. Put the important words first.
Simple and personal wins. The most famous test in email history: the Obama campaign’s subject line “Hey” raised $2.5 million more than the runner-up. Nobody expected it.
Negative can beat positive. “Don’t make this mistake” often beats “How to do it right.” People hate losing more than they love winning.
Old spam-word advice is dead. Modern filters barely read your words. They judge whether people want your email. Send wanted email and you can say “free.”
That little grey line after the subject? Write it on purpose. Adding intentional preview text lifts opens by about 5%, takes 30 seconds, and almost nobody does it. It’s the cheapest win in this book.
Write to one person. Picture a real reader before you write. The email should read like a message meant just for them.
One job per email. Busy people scan. Give them one clear thing to do and make the button obvious.
Ask for replies. Replies are the strongest signal to Gmail that people want you. They also move you toward the Primary tab.
Plain can beat pretty. In tests, a plain-text email sometimes beats the designed one — especially in B2B. It feels personal. Test yours.
Short vs. long: it depends. Simple products sell with short copy. Big, considered purchases need more detail. Test 100 words against 400.
Last thing: send emails people expect. Answer “what does this subscriber need right now?” — not “what do we want to say this week?” Brands that make that switch see 20–40% more email revenue without sending more email.
Specificity. A subject line that names the thing, the number or the change outperforms vague curiosity, because curiosity gaps that do not pay off teach recipients to stop opening. Length matters far less than clarity, though mobile clients truncate around 40 characters.
A recognizable person at the company usually performs best, as long as it stays consistent. Recipients scan the sender name before the subject line, so changing it frequently costs more in recognition than any individual send gains.
Preview text is the snippet inbox clients show after the subject line. It is effectively a second subject line and one of the highest-leverage 40 characters in an email, yet most senders leave it repeating the subject or defaulting to a view-in-browser link.
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