Key facts
- Subject lines that work are short and plain: a topic, their company with a topic, or a simple question.
- Subject tests are live in Buzz Send, so you can see which wording gets more replies.
- Buzz sends follow-ups as replies in the same thread.
Which subject lines work?
Subject lines that work are short and plain: a topic, their company with a topic, or a simple question.
- The topic: "spring hiring".
- Their company plus a topic: "Acme onboarding".
- A plain question: "right person?"
Which ones hurt?
- "Quick question!!!"
- "Re: our call" when there was no call.
- "Increase revenue 300%".
Misleading subject lines also break CAN-SPAM. Source: FTC
Does Buzz test subject lines?
Yes. Subject tests are live in Buzz Send, so you can see which wording gets more replies.
How to write a cold subject line
- Pick the topic
The one thing the email is about.
- Cut to five words
Or fewer.
- Write it in lower case
Like a note to a colleague.
- Test two versions
Keep the one that gets replies.
When does Buzzlist fit, and when does it not?
It fits when
- You want subject tests built into sending.
It does not fit when
- You write marketing newsletters, where different rules apply.
Questions people ask next
Should I use their first name?
It can help, but company or topic often reads as less salesy.
Do follow-ups need a new subject?
No. Buzz sends follow-ups as replies in the same thread.
Are emojis OK?
Avoid them in cold email.
How long should the subject be?
Two to five words.
Sources
Checked October 9, 2026. Rules change, so read the source before you rely on it. This is general information, not legal advice.