The subject line decides whether your carefully designed email gets read. A few habits make a big difference.
Be specific
"October newsletter" tells people nothing. "3 new templates and a 20% autumn discount" tells them why to open. Lead with the most valuable thing inside.
Keep it short
Phones show around 35 to 45 characters. Put the important words first and use the preheader to continue the thought.
Sound like a person
Write the way you would to a customer you know. Personalisation helps when it is natural: Ana, your report is ready works; forcing a name into every subject does not.
Avoid the spammy stuff
All caps, piles of exclamation marks and "FREE!!!" make you look like the emails people delete. One emoji can add personality; five look desperate.
Test instead of guessing
Run an A/B test on a sample of your audience and let the winner go to everyone else. Compare on clicks rather than opens, since privacy features make opens unreliable. Stuck for ideas? The Suggest button writes options from your email's content.