Why Subject Lines Matter

The average professional receives over 100 emails per day. Most people decide whether to open an email based entirely on the subject line and sender name. If your subject line is vague, generic, or too long, your carefully written message may never get read at all.

Writing a good subject line is a small skill with disproportionate impact.

Five Principles That Work

1. Be specific, not clever. "Quick question about Thursday's meeting" beats "Hey!" every time. Your subject line should tell the recipient exactly what to expect. Save wit for the body of the email.

2. Front-load the key information. Many email clients truncate subject lines after 40-50 characters, and mobile screens show even less. Put the most important words at the beginning. "Budget approval needed by Friday" works. "I wanted to check in about something regarding the budget" does not.

3. Include a deadline or timeframe when relevant. "Feedback on proposal - need by Wed 3/11" is more likely to get a timely response than "Feedback on proposal." People triage by urgency, and your subject line should make urgency visible.

4. Use brackets for categories. In team environments, prefixes like [Action Required], [FYI], or [No Response Needed] help recipients prioritize instantly. This is especially valuable in high-volume workplaces.

5. Avoid all caps and excessive punctuation. "URGENT!!!" triggers spam filters and annoys readers. If something is genuinely urgent, say so plainly: "Urgent: server outage affecting customer portal."

Common Mistakes

"Following up" tells the reader nothing. Following up on what? "Re: Re: Re: Re:" chains should be broken with a fresh subject line when the topic has shifted. "No subject" is never acceptable in a professional context.

The Test

Before sending, read your subject line and ask: if I received this from someone I don't know well, would I open it? Would I know what it's about? Would I know if it's urgent? If the answer to any of these is no, revise.

Good email writing starts before the greeting. It starts in the subject line.