It’s time to talk about your dirty list (and what you can do about it)

email list optimization

If the only metric you’re measuring is the size of your list, you’re in trouble. Because a big list doesn’t equal a good list. Actually, it can translate into the exact opposite. That’s why it’s crucial to regularly scrub your email list to trim the fat and hone in on the readers that matter most. 

What does scrubbing your list even mean?

We take showers to get rid of the grime. Scrubbing your email list is essentially the same thing. It just means that you regularly go through and remove both inactive and inaccurate emails so that your list is squeaky clean. 

You can do this manually, automatically, or using a combination of both strategies.

How can I tell it’s time to clean my list?

The easy answer is that everyone needs to clean their lists regularly. But since we live in a world where only about a gazillion things are on our to-do list, far too many email marketers keep putting it off. Here are a few warning signs that you simply can’t wait any longer: 

  • Your open rates keep finding a new bottom
  • Your email click-through-rates have dropped and stayed down
  • Your spam complaints are rising
  • Your bounce rates are through the roof

Even one of these is a sign that you can’t waste time. But if you’re suffering from two or more of these symptoms, it’s time to re-arrange your schedule and make scrubbing your list an urgent priority.

There are big rewards for tackling this chore

By nature, humans will go to greater lengths to avoid pain than they will to find pleasure. The great news is that scrubbing your email list will accomplish both goals in just one effort. How’s that for a dose of motivation?

  • Regular scrubbing will lower your email marketing costs while raising your return on investment
  • You’ll see a dramatic drop in your spam complaints, and suddenly email providers will like you more
  • You’ll enjoy a rapid rise in both your open and your click-through rates

And having seen your responses to recent surveys, I know that you want all three of those rewards.

We’ll address the mechanics of scrubbing your list in just a moment, but first, let’s talk about two things you need to do before you start the scrub. 

2 things to do before you scrub your list

The first thing you need to do is take a look at your hard and soft bounces. Most email clients will automatically remove hard-bounce emails from your list. Soft bounces, however, represent email addresses showing a temporary issue. 

Hard bounces need to be removed without delay. Soft bounces should be monitored. You may even want to create a dynamic suppression list that doesn’t email those members again until a certain time period has passed. 

The second strategy you’ll want to deploy is a re-engagement campaign. 

Just because someone is inactive right now doesn’t mean they have to stay that way. 

This allows you to place inactive subscribers into an email drip (or journey, or workflow, or whatever jargon your email client uses) that gives them one more chance to engage before you go through and cull your list. 

Use a clever “can’t resist” subject line and then give those readers a choice, do you want to keep getting emails from us? Yes or no. Those who click yes have now opened and engaged. Those that click no get unsubscribed. 

Better yet, you can run your re-engagement campaign through Inbox Mailers and do it with a higher probability of getting opened without damaging your deliverability.

You can find out how that behind-the-scene magic works (and increase open rates to 50-70%) by getting your hands on this comprehensive guide

And those that didn’t do anything, well, we’ll talk about what we’ll do with them in just a second. 

5 tips for starting your scrub

Tip #1: Prioritize based on frequency

When it’s time to scrub your list, you’ll want to start with the lists you use the most and that have the most actively engaged readers. But you won’t want to stop there. Just prioritize the scrubbing based on the frequency with which you send. Begin with the most frequent and end with the least frequent lists. Depending on how you segment your list, you may have a dozen or more lists in need of a good cleaning. 

Tip #2: Next, get busy removing duplicates

It doesn’t make any sense to send six emails to the exact same subscriber. But it happens. That’s because people might forget that they’ve already subscribed, or your messages may be hiding in promotional or spam folders. So, that reader heads back to your opt-in page and subscribes again. And maybe again. Scrubbing those duplicates is a fast and easy way to increase your list’s efficiency and ROI. 

Tip #3: Find and remove “spammy” email addresses

Doing this manually can be a nightmare, but the good news is that there are list cleaning services out there that can automate this process. Info@ email addresses are often “catchall” addresses. Then there are email “aliases” people use to sign up for sexy lead magnets that look like this:, but it isn’t just +spam that they use. Finally, specific domains are often tied to bots or fake email addresses. Doing this manually can be tricky, but there are a host of services out there that can help you automate the process. 

Tip #4: Make sure that you’re removing people who have unsubscribed

This seems like a no-brainer, but sometimes, big stuff falls through the cracks. Take a moment to double-check that anyone who unsubscribes has been removed from your list. If you send emails from multiple channels, you may want to create an internal policy for handling unsubs from one channel in the other channels. If they unsub from one channel, will you unsub them from all channels? If not, why not? If you keep an unsubscriber on other channel lists, make sure you clarify after the unsubscribe that they’ve only unsubscribed from one channel and then give them the option to get removed from the rest if that’s what they want. No sense in wasting sends on folks who don’t want them or (worse) will complain that you’re spamming them after they unsubscribed. 

Tip #5: Find and replace common typos

Typos happen. That’s just a fact. And people even make typos when they’re adding in their own email addresses. It’s all too easy for gmail to become gamil or some other variation. Once you’ve tackled the first four email scrubbing recommendations, devote some time to cleaning up contacts with typos so that they’ll actually get the messaging they want. After all, that accidental typo could keep your emails away from someone desperate to buy. 

If all of these tasks seem too daunting to tackle yourself, you don’t have to. Several email list cleaning services can help you make it happen with just a simple click. The best ones aren’t free, but they are worth every penny you’ll spend. After all, time is money.

Here are a few of our favorites:

It’s also worth noting that each one of these services specializes in something a little bit different. That’s why we recommend you use more than one to ensure you’re getting exactly what you need. 

You might also be surprised to learn that you’re already paying for a list scrubbing service through your ESP. So, double-check what options they already have available that you might have overlooked before. 

So, now that you’re all out of excuses, what are you waiting for? Get busy scrubbing your list and reaping the rewards. 

But don’t stop there. Once you’ve tackled your list hygiene, you need to start zeroing in on your list engagement. If you’re sick and tired of stressing out over lackluster open rates, it’s time to accept the fact that timing is everything. And we’re not talking about Tuesday at 10:00 am, either. The best time to send an email is when your subscriber is already in their inbox. It’s like giving a triggered send a nice dose of steroids. 

And you don’t even need to know how to code to unlock the magic. If you want more eyeballs on your offers, more clicks, and higher revenue, then this is the secret ingredient you’ve been missing. 

Picture of John Gardner

John Gardner

John Gardner is an expert email marketer and co-founder of Inbox Mailers. He specializes in email segmentation and improving overall deliverability, helping top brands and businesses optimize their email marketing strategy.