How to write a sales email subject line
The subject line decides whether your carefully written email gets read at all. The best sales subject lines feel personal and specific, like a note from a colleague, not a marketing blast. Short, honest, and relevant beats clever and salesy almost every time.
Short answer
Write a sales email subject line that is short (a few words), specific, and honest, referencing something real about the prospect rather than hype. Lowercase, question-style, and personalized subjects often outperform polished marketing copy. Avoid clickbait the body cannot deliver, and test variations to learn what earns opens from your audience.
Step by step
Keep it short
A few words, so it reads fully on mobile where most email is triaged. Long subject lines get truncated and skipped.
Be specific and relevant
Reference something real about the prospect or their company. Specificity signals a human wrote it for them, which drives opens.
- Short: a few words, mobile-friendly
- Specific: reference something real about them
- Honest: no clickbait the body cannot deliver
- Personal tone over marketing polish
Sound human, not like marketing
Lowercase, a genuine question, or a casual reference often outperforms a polished promotional subject. Aim for colleague, not campaign.
Avoid clickbait
Never use a subject the body does not deliver on. A "re:" trick or fake urgency gets the open but destroys trust and tanks replies.
Test and learn
Try variations and track open rates by subject style for your audience. What works varies by segment, so let data guide your defaults.
How Ardovo helps
Ardovo tracks open rates by subject-line style across your outreach, so Rook can tell you which subject patterns earn opens from each segment and draft personalized, specific subjects rather than generic ones.
Frequently asked questions
What makes a good sales email subject line?
Short (a few words), specific to the prospect, honest, and human in tone. Referencing something real about them signals a person wrote it. Lowercase and question-style subjects often beat polished marketing copy because they feel personal rather than promotional.
Should I use clickbait subject lines?
No. Tricks like fake "re:" prefixes or manufactured urgency may earn the open but the body cannot deliver on them, so you destroy trust and tank reply rates. A subject line that honestly reflects a relevant, specific message performs far better over time.
How long should a subject line be?
Short enough to read fully on a phone, usually just a few words. Most sales email is triaged on mobile where long subjects get truncated. Brevity plus specificity earns the open; length and hype get skipped or filed as marketing.