Personalised subject lines lift replies by 30.5%

From the same Backlinko and Pitchbox twelve-million-email dataset, outreach subject lines that incorporated the recipient's name, site name, or a reference to recently published content lifted reply rates by 30.5 per cent against the generic template baseline. The effect is independent of body-copy personalisation and stacks with it. Subject-line personalisation works because it changes whether the email gets opened at all; reply-rate lift downstream is a near-mechanical function of the opens being human-targeted rather than template-blasted. For outreach programmes already running personalisation in the body, ignoring the subject line leaves measurable reply volume on the table.