Why cold email subject lines should look boring
A cold email competes with internal mail, not with marketing newsletters. Subject lines that look like a colleague wrote them (lowercase, short, no punctuation tricks) get opened because they blend in. Subject lines that look like a campaign get skimmed and deleted, or worse, reported.
That is why Nova writes in sentence case, avoids exclamation marks and keeps every line under 50 characters. On a phone, most inboxes show roughly 35 to 45 characters before truncating, so the important word needs to come early.
- Sentence case or lowercase; never Title Case or ALL CAPS.
- No emojis, no brackets, no 'RE:' unless it really is a reply.
- Put the specific word (their company, the problem) first.
- Avoid words that promise money, urgency or freebies.
The five styles and when to use each
Curiosity lines open a loop the reader wants closed, and work best when the email body pays it off in the first sentence. Value lines state the outcome plainly and suit audiences that are tired of clever. Question lines are easy to answer and easy to forward to the right person.
Personalised lines use a merge tag or a real trigger (a hire, a funding round, a launch) and get the strongest results when the trigger is genuine. Direct lines simply say what the email is about; replies to those are fewer but better qualified.
curiosity the week you lose per client
value 12 domains, DNS done, under ten minutes
question still doing SPF and DKIM by hand?
personalised saw the SDR hire at {{company}}
direct domain setup for {{company}}How to A/B test subject lines properly
Test one variable at a time and give each variant enough sends to mean something. Split the same list, same body, same send window, and change only the subject. Judge on replies and positive replies, not opens; open tracking is unreliable now that many mail clients pre-load images.
Rotate winners into new tests rather than settling. A subject that worked for one persona often flops for another, so keep a small bank per audience. If a subject line wins on opens but loses on replies, it is baiting people; drop it.
- Minimum two variants, one variable.
- Same send window and same mailboxes for both.
- Measure reply rate, then positive reply rate.
- Retire a line after it has been seen by the same accounts twice.
