Reply rate

Reply rate is replies divided by emails sent or delivered, times 100. Pick one base and keep it. Using delivered emails removes bounces and gives a fairer picture of how your message performs. Count real replies, and leave out out-of-office messages and automatic bounces.

Split replies into positive, neutral and negative. A high reply rate that is mostly 'remove me' is not good news. The rate that matters most is the share of positive replies.

Reply rate is more useful than open rate because opens are unreliable. Many things change it: the list, the offer, the subject line, the length, the number of follow-ups and the sending setup. Change one thing at a time, wait for enough sends to judge it, and compare like with like. A test on 30 emails says very little. If replies fall, check bounces and inbox placement before you rewrite the copy.