<b>Subject lines under 6 words reply at 11.4%; over 10 words, 4.1%</b>

<b>Subject lines under 6 words reply at 11.4%; over 10 words, 4.1%</b>

Subject length is one of the cleanest levers in outreach. Across 142,000 emails (8-month window, observational):

Reply rate by subject word count climbs as you shorten — from 4.1% at 11+ words, to 7.8% at 7-9 words, to 11.4% at 5 words or fewer. The relationship is near-monotonic across the range.

Short subjects read as human and specific; long ones read as pitches and get archived unopened.

Question-form subjects under six words performed best of all in the sample.

<b>Cap outreach subject lines at five words, ideally as a question.</b>