Unsubscribe means removing one’s email address from a mailing list so as not to receive further communications. Every email campaign must include an “unsubscribe” link, which automatically changes the subscriber’s status from “active” to “unsubscribed” in the sender’s system.

The “unsubscribe rate” is the percentage of people who opt out. It is calculated with the following formula:

Number of unsubscribed / Delivered emails x 100 = Unsubscribed rate %.

The average unsubscribe rate varies by niche, but less than 1% is considered reasonable. A fluctuating or steadily-increasing unsubscribe rate is a red flag. Unsubscribe rates can be reduced by: