Calculating Bounce and Non-Bounce Rates for Your E-Mail Marketing Campaign

By John Arnold

You want all your e-mail marketing messages to get to their intended targets. Unfortunately, that rarely happens, and some of your messages come back as undeliverable, or bounced.

Figuring your bounce rate

The bounce rate is the number of e-mails returned as undeliverable expressed as a percentage of total e-mails sent. You can calculate your bounce rate:

  1. Divide the total number of e-mails that bounced by the total number of e-mails sent to get the total number of bounces per e-mail.

    For example, if you send 100 e-mails and 20 of them bounce, you bounced 0.2 e-mails for every e-mail sent.

  2. Multiply your bounce per e-mail rate by 100 to get your bounce rate as a percentage.

    For example, the bounce rate for 0.2 bounces per e-mail is 20 percent.

According to Epsilon’s Email Trends and Benchmark guide (2010), the average bounce rate for commercial e-mails is anywhere between 2 and 15 percent, depending on the industry.

Calculating your non-bounce total

Non-bounce total is the number of e-mails that were not bounced and therefore assumed delivered. You calculate your own non-bounce total by subtracting the total number of bounced e-mails from the total number of e-mails you sent. For example, if you send 100 e-mails and 20 of them bounce, your non-bounce total is 80.

Non-bounce total is sometimes expressed as a percentage, but the non-bounce total is more useful as a real number because e-mail open rates are actually based on your non-bounce total instead of the total number of e-mails sent.

Your non-bounce total isn’t the same as the total number of e-mails delivered. Some e-mails aren’t reported as bounced because software on the user’s computer or a mobile device bounced it — not an e-mail server — and some e-mail servers falsely deliver your e-mail to a junk folder that users can’t access.

Even though you can’t be sure whether your non-bounced e-mails are being delivered, you can assume that your non-bounced e-mails are reaching your audience until you have good reason to believe otherwise.