How to clean your email list (and keep it that way)

So far, we’ve covered:

  • Email regulations
  • Getting whitelisted
  • Staying out of the spam folder
  • And checking for spam before sending your campaign

If you notice, all that was focused on prevention, which is the best medicine. But like I said before, just because you listen to the doctor and take care of yourself, doesn’t mean you won’t get a little sick every now and then.

In this and the following lessons, we’ll focus strictly on the list, how to clean it and how to keep it healthy.

Let’s get started!

What is a Bounce?

A Bounce (fancy-pants industry terminology) is when you send an email to an address that is not receiving because:

  • Non-existent email address – Could mean there is a typo or the address no longer exists
  • Undeliverable – The email server is temporarily unavailable, was overloaded, or couldn’t be found
  • Mailbox Full – The user can’t get anymore messages because the inbox is full
  • Blocked – Your address was blocked by the user

There are 2 kinds of Bounces:

  • Soft: It’s temporary, a server failure or a full mailbox
  • Hard: A permanent issue, address is invalid or no longer in use, domain no longer exists or a simple typo


Why is it crucial that you stop sending to these individuals?

Because Bounces lower your delivery rate and this can damage your reputation as a sender and you might end up being blocked by an ISP.

Another reason to me is that these people are not seeing your messages, the chances of achieving your goal, whatever that is, are zero, zip, nada!

Bounce Rate

Bounce Rate is the metric that measures the bounces on each campaign you send. If you send a campaign to a list of 11,466 and you have 36 bounces, you have a Bounce Rate of 0.3%.

Bounce Rate

How to monitor it

In this video, I show you how to look at your campaign bounce rate on both Mailchimp and Aweber.

But, what is a normal bounce rate?

But, what if you have a bounce rate of 0.3% or 2.0% or 14.5%. What is consider normal?

Let’s start with a bit of common sense. In the video, I showed you 2 different case, a 0.3% rate in a campaign sent to 11,466 people and a 2.0% on a campaign sent to 49. You see the problem?

The 1 person that bounced in my 49 people campaign has a much bigger impact. Think about it, if you have a list of 100 people and 20 are bouncing, that’s horrible. I don’t need to research what a good bounce rate is, it’s common sense.

Now, we also have studies that have been conducted to measure bounce rate.

Bounce rate stats by industry

That gives you a pretty clear picture, right? I’d say…

Let’s keep it under 1%.

And how do you do that?

Clean up time!

Okay, so I’d say we now have a pretty good understanding of what a Bounce is, how to monitor your rate and why you need to try to keep it down. Now, let’s get into some cleaning spring!

Some ESPs like Aweber will automatically clean the list for you if certain criteria is matched, and others like Mailchimp will put that responsibility on your side.

Here is how Aweber removes undeliverable addresses in their own words: “We will continue to send your messages to a subscriber until they are undeliverable 3 times in a 60-day period. Once they are undeliverable 3 or more times in 60 days (and there has been at least a week between the first and most recent bounce), that person will be unsubscribed from your list.”

These subscribers are not deleted, they are just “Unsubscribed.” Once the status changes you are no longer sending campaigns.

You also have the option to manually unsubscribe or delete them from the list. In this video, I show you how to do that.

Another way of keeping a healthier list is to get rid of the undeliverables.

An “undeliverable” simply means that the email is no longer reaching its destiny, this can happen for different reasons like a typo in the email address, the account was closed, the server is down or your emails have been blocked by the recipient.

Either way, this has a negative impact on your delivery rate and it can affect your sender’s reputation.

3rd-party services

If your ESP doesn’t clean the list for you or doesn’t give you the option to do it yourself, you are going to have take matters in your hands and go to a 3rd-party service.

One thing to keep in mind is that, even if your ESP doesn’t do this, you can still raise a red flag in their system, get a warning or suspend your account for having too many undeliverable addresses in your list.

These are some of the services that can help you identify and remove invalid email addresses from your list.


The process is simple, you export your list from the ESP into a CSV file and upload it in the same format on one of these services. BriteVerify gives you a quote for the cost before you run it.

These services have different pricing but the average cost is $0.01 per email address and it can lower depending on the size of your list.

Is it expensive? Maybe, it really depends on the list, but I think putting your sender reputation on the line to save a few bucks can be even more costly.


You have some cleaning to do. Don’t put this off because you might be sending emails to undeliverable addresses right now without even knowing.

Here’s what we’ll do:

  1. Go to your ESP
  2. Look at your campaign analytics > Bounce Rate
  3. Find out what the options are to remove the undeliverable addresses from your list
  4. Remove them
  5. If they don’t offer a bulk removal option, see if you can at least remove them manually one by one
  6. No luck? Go to a 3rd-party service and get a quote

But here is the most important task, you need to do this periodically. Keep monitoring every campaign you send out and, depending on the rate, you’ll be able to decide if you need to do this every 3 months or 6 months.