What are catch-all emails and how to manage them

Catch-all email servers allow businesses to ensure that all messages sent to an incorrect email address on their domain can still be delivered. Catch-all email addresses help companies receive important messages that otherwise would go undelivered. At the same time, these email addresses also end up on your email lists and run the risk of being invalid, which could put you at the mercy of Internet Service Providers (ISPs) like Gmail. 

Fear not! Managing catch-all emails is easy, and you’ll thank yourself for it in the long run. Despite the idea that they enable you to reach inboxes no matter what, leaving catch-all email addresses unmonitored in your email list can have a detrimental effect on your deliverability

Confused? Don’t worry! If catch-all emails have left you scratching your head, you’ve come to the right place. In this article, we’ll explain what catch-all emails are, their purpose, and how to manage them for a healthy email list. 

Catch-all email addresses—also known as accept-all emails or wildcard email aliases—are email addresses belonging to a catch-all mail server. These accept emails sent to any address belonging to the domain name. 

That’s right—any email address. Even non-existent ones. This could apply to email addresses that contain typos, or even addresses that are completely made up. 

For example, let’s say that the catch-all domain is yourdomain.com. You only have email addresses for your three employees: [email protected], [email protected], [email protected], as well as a catch-all inbox for [email protected]. A person could send an email to [email protected] or [email protected], and the email would land in the “contact” inbox.

You may be thinking that this defeats the purpose of email addresses in the first place but catch-all email servers were created with the best intentions. 

Companies use catch-all email servers so that any emails sent to a non-existent or incorrect email address can still be delivered. It’s a way of ensuring that important email messages don’t go undelivered. This can be especially important for eCommerce stores not wanting to miss a lead, or questions directed to the support team.

When sending emails to a catch-all email address that doesn’t exist, the message is forwarded to a single inbox created especially for these types of emails. Most businesses then check the inbox periodically to see if anything of interest has landed there.

That sounds like a great solution to avoiding any missed communication, right? Unfortunately, catch-all email servers quickly became a haven for spammers. This led companies to abandon or pay less attention to their catch-all inbox, as they became overwhelmed by unsolicited emails.  

If you’re wondering how common catch-all emails really are, we’ve got some data that’ll spill the beans on what the average email list looks like.

The chart below details the email status of all emails that MailerCheck has ever verified. As you can see, catch-all takes up quite a significant chunk of the pie, with 8.6%.

Pie Chart showing email statuses including catch-all emails found in MailerCheck customer lists

When we take a look at the median value for catch-all emails in each list across all customers, this figure increases to 15.25%, with an average of 541 catch-all emails per list! And in an interesting twist, catch-all emails are more often found in smaller lists.

What does all this mean to you? Catch-all emails are too common to be ignored and there’s no way of knowing if a subscriber belongs to a catch-all domain at first sight.

A lot of businesses use catch-all email. With no way to tell which catch-all email accounts belong to real people and which are non-existent, removing them from your list might be a big mistake. 

These email addresses could belong to real subscribers who signed up for your content and may convert into paying customers. Not to mention, if they are in fact engaged subscribers, they’ll be helping to improve your sender reputation and deliverability by contributing to your open-rates. 

While the benefits mentioned above might be compelling, there are a number of disadvantages that mean you can’t just leave catch-all emails on your list and forget about them. 

Catch-all emails can be detrimental to your sender reputation. While your email might land in the catch-all inbox, if the email address is invalid, there is a good chance that it won’t be opened. This will skew your engagement rates, and hurt your marketing campaign performance. 

And to make things even more complicated, despite the fact that “accept-all” suggests all emails will be delivered, there is still a chance that your email could bounce. In fact, some companies configure their catch-all inboxes to initially accept all emails, only to reject them later, or set limits on catch-all rates, resulting in a hard bounce. *Le sigh*

Furthermore, Email Service Providers (ESPs) like MailerLite use bounce rate as a metric to qualify your use of their services. If that bounce-rate creeps up too high because of catch-all email bounces, the ESP might terminate your account.

Of course, all of this depends on whether your catch-all emails are valid or invalid, and whether your email list is clean or not. Luckily, there’s a simple way to find out!

Let’s get one thing straight—emails belonging to a catch-all server are unverifiable—there is no way to know if they are valid or invalid. No tool on the market can do this because they can’t use SMTP to check out what’s happening in the inbox. 

However, you can run your email list through an email validation tool, like MailerCheck, to check which emails belong to a catch-all domain, and then build a strategy for managing these email addresses

Step 1: Check your email list health

Did you build your email list from scratch through sweat, blood and tears? Is your list opt-in, or even better double opt-in? Or perhaps you might have filtered out risky emails in real-time using an email verification API. If so, there is a good chance that most of the catch-all emails on your list are valid. You have a clean list, well done!

Learn about how to create opt-in forms that work under GDPR.

If you acquired your list through more questionable means, for example, if you purchased your email list (read more here on why this is a big mistake!), then stop right there. ✋ Not only will this skew your engagement metrics and potentially ruin your brand reputation, but also no email marketing software will allow it. Plus, there’s a real risk that you’ll hit some spam traps along the way! You should work towards building a healthy list from scratch. 

To gain deeper insights into your email list, run it through MailerCheck. It will tell you how many emails in your list are valid, and how many show cause for concern due to being catch-all, syntax errors, not found, and more. 

Step 2: Test and improve

Once you’ve ran your email list through MailerCheck, you’ll be able to see how many catch-all emails your list contains. A good way to weed out any invalid email addresses, and save those that are valid, is to carry out tests in your campaigns. 

To keep your bounce rate low and your ESP happy, you can do this by adding only a few catch-all emails to each campaign. You can then monitor which catch-all recipients open the email to determine which are valid emails, and transfer these to your main list while removing the invalid ones that bounce. 

Keep doing this until you have worked through all the catch-all emails that MailerCheck has identified.

Time to check your list

For something as “passive” as catch-all emails, they sure do throw a spanner into the works, right? But don’t worry! Now that you’re armed with the knowledge and tactics needed to face catch-all emails head-on, you’ll be able to develop a strategy that fits your email marketing goals and helps you to make informed decisions about how you treat accept-alls.

The first step is verifying your email list! Sign up to MailerCheck for free and start verifying your subscribers today. 

Amy Elliott
I’m Amy, Content Writer at The Remote Company. As a child, I dreamt about writing a book and practiced by tearing pages from an A4 notepad and binding them with sugar paper. The book is pending but in the meantime, I’ve found a passion for telling a different kind of story-the brand story-by writing fun, valuable, human content.