Building an email list is a time consuming job, but once you have one it’s not quite as simple as stopping there. Email addresses can become inactive, users can input the wrong one into your sign-up forms, and consumers can lose interest in your marketing emails. Sometimes those users can be re-engaged, but if they can’t you need to cut them from your lists in order to maintain good email hygiene.

What Is Email Hygiene?

Email hygiene, also known as email list hygiene, is the practice of keeping your email lists clean of any addresses that aren’t going to engage with you. Keeping your list clean is a good way of making sure you’re trusted by internet service providers (ISPs), as anyone sending out lots of emails that don’t get opened will be marked as suspicious and may even start marking you as spam.

Oftentimes, ISPs will turn inactive email addresses into what are known as spam traps. Essentially, any IP address that sends emails to a spam trap is assumed to be sending emails indiscriminately and without regard for whether or not the recipient wants to receive them - exactly as spammers do - and will have their mail marked as spam. This hurts your reputation, and can even get you blacklisted

There’s no set time at which you have to clean your email lists. Some say the more the better, but drawing a line and making it routine is often the best way to go. Remember though, some users who still want to engage with you might take breaks or forget to respond, so the time period before an address is cut from your list should be long enough to account for this.

How Can You Keep Your Email List Clean?

There are several ways to spot those who need to be removed from your lists, some of which should be done more often than others.

1. Remove subscribers who don’t interact with you

Taking anyone who doesn’t interact with you off your list is an obvious step. This is best done every few months or so, in order to catch those addresses who were interacting with you before but are no longer doing so. This is a necessary tactic to avoid spam traps, but also to avoid a low reputation from sending emails that don’t get opened.

Using filters on your email manager, you can check who has opened, responded etc to what in a specified time frame. What that time frame is is up to you and your business model - those who buy rarely but buy big are worth keeping on your list even if they haven’t interacted in a while. Conversely, if you’re a business that relies on consistent, smaller sales, you might want to be cutting emails off your list for shorter periods of non-interaction. It’s up to you at the end of the day, as there’s no real right answer here.

1. Use third party email validation

Email validation is the process of checking whether or not email addresses on your list both exist and are active. It’s a useful process to have when you’re checking through new email sign-ups, but can help with the bulk of the list too since validation services can process entire lists quite quickly and cheaply.

The criteria that the validation services use are all fairly similar - checking domain names are valid, checking that an email with that address exists within that domain, checking for catch-all policies that are often the mark of spam traps and more.

1. Remove those addresses that repeatedly soft bounce your emails

Soft bouncing refers to a mailbox that can accept your email, but doesn’t. This can be for a few reasons such as server downtime, a full inbox or error in communication. While these soft bounces don’t hurt your reputation themselves, they can turn into hard bounces that will.

Using an email management software once again, you can filter out those email addresses that repeatedly soft bounce your mail and remove them. When exactly you remove an address is once again up to you, but repeated bounces over a long period of time indicates that you’re dealing with an account that might not be used anymore.

1. Make unsubscribing easy

Don’t want to spend time cutting email addresses off your list? You can get consumers to do it themselves. While seeing former customers unsubscribe from your mailing lists might be a bit of a downer, it’ll definitely help keep your lists clean and stop you bothering someone who doesn’t want to see your content at the same time.

Making your unsubscription process easy to use and easy to see is crucial here. If your big red button is easy to see, most people will press it rather than simply send you into the spam filter, saving themselves time and effort and stopping you from taking a hit to your sender reputation.