4 Simple Ways To Fix an Invalid Email Address in Your List

What is an invalid email address?

Some invalid addresses are easy to spot, such as addresses without an @ symbol. Others can look correctly formatted but still fail because the domain has no mail server, the mailbox no longer exists, or the address belongs to a disposable email service.

Are invalid emails bad for your lists?

Invalid emails are a deadweight on your list. Many ESPs charge per contact, so if you keep these in your subscriber base, you pay without ever getting a return — these addresses are simply inaccessible.

They also return hard bounces, which can hurt deliverability and sender reputation. If hard bounces keep building up, future campaigns may become harder to deliver.

Are invalid emails common?

According to turboSMTP’s dataset of more than half a million email addresses collected through online forms, 22% were incorrect or invalid: 15% contained typos, and 7% were abandoned or inactive.

That does not mean every list will lose the same share of contacts, but it shows how quickly invalid addresses can build up when signup forms, imports, and old contacts are not checked regularly. Even a smaller share of hard-bouncing addresses can hurt email deliverability and sender reputation.

Common reasons for invalid email addresses

We’ve touched on the reasons why emails may be invalid, but let’s go over the reasons in a bit more detail.

Email has typos or an invalid email format

Only email addresses that follow the name@domain.com syntax are considered valid. In the local part, there can’t be spaces, multiple @’s, or no @ at all, a double dot, or extra special characters. 

Here is a non-exhaustive list of various mistakes in an email address syntax:

• onlynamewithoutatanddomain
• #@%^%#$@#$@#.com
• ”(),:;<>[]@domain.com
• @domain.com
• name.domain.com
• name@domain..com
• name@domain@domain.com
• .name@domain.com
• name.@domain.com
• name@-domain.com
• name..name@domain.com
• あいうえお@domain.com
• name@domain.web
• name@111.222.333.44444
• Abc..123@domain.com
• this is”really”notallowed@domain.com 

There are exceptions. According to Google Support, if someone’s private address is andrewdoe@gmail.com and somebody accidentally typed in additional dots, e.g., andrew.doe@gmail.com, the person will still get that email. 

However, if a company or school uses Gmail to administer emails, dots do change the address, and a dot in andrew.doe@selzy.com instead of andrewdoe@selzy.com will be considered a mistake and render the address invalid.

Domain with the email address has been deleted

Some companies create custom domain names, such as name@selzy.com, where “selzy” is the domain. In case the company ceases to exist or wants to move its employees’ mailboxes to a new provider, it might delete or deactivate the existing accounts on the company’s server. All of this renders the email address inactive.

When a person leaves their workplace, their employer might delete their account and the inbox with it. Some providers, like Microsoft, offer an option to retain a former employee’s inbox with all its content for some time for regulatory or other reasons. Such a soft-deleted mailbox can be restored within a month, but it is still inactive.

Email has been changed or deleted

People can change their minds and either change their usernames or move to another domain and abandon the initial inbox they had. This means that your marketing communications won’t reach them. However, there’s more than one reason for deletion. Some providers reserve the right to delete or deactivate accounts after a long period of inactivity:

• Gmail retires an account if it has been inactive for two years. 
• Microsoft’s Outlook and Hotmail, and Yahoo deem an address inactive after a whole consecutive year or more. 

Person used a disposable email

People use disposable emails when they are reluctant to share personal information or want to avoid spam. Disposable, burner, or throw-away email addresses are temporary. They expire after 10 minutes, one hour, or a couple of days at most. 

Disposable email addresses harm any marketing campaign, at first boosting signup numbers but affecting long-term engagement rates. 

Tips for fixing invalid email addresses

It’s easy to remove invalid emails if you regularly clean your email list. However, if your cleanups often find a lot of inactive or invalid addresses, it is better to prevent bad contacts from entering your subscriber base in the first place.

Start by separating fixable mistakes from addresses that should not receive campaigns anymore. Obvious typos, such as gmial.com instead of gmail.com, can sometimes be corrected manually if you have enough context. Addresses with non-existent domains, deleted mailboxes, repeated hard bounces, or disposable domains should be removed from active sends or moved to a suppression list. Then prevent the same issue from coming back with double opt-in, signup-form validation, and regular list cleaning.

Check manually if you have entered the correct email address

Human error is a real thing. Everyone makes mistakes, whether the person entered their address in a hurry or your finger slipped on the keyboard when you recorded their email by ear. Anyway, it will not hurt to double-check that you spelled the address correctly. 

If their username is the same as their actual name, compare the spelling; check if there are common typos in domain names, or if there are random dots and other special characters.

Check the address through the email verifier

Email validation and email verification solve different parts of the problem. Validation checks whether an address looks correctly formatted, for example whether it has a local part, @ symbol, domain, and top-level domain. Verification goes further and checks whether the domain can receive mail and, when possible, whether the mailbox itself exists.

A valid-looking address can still be risky or undeliverable if the domain has no MX records, the mailbox was deleted, or the address belongs to a disposable email service. That is why large lists need more than a manual syntax check before a campaign send.

Using a verifier helps reduce hard bounces, protect sender reputation, and keep campaign metrics cleaner.

Record people’s other contacts besides emails

As we can see, collecting email addresses may not be enough to reach a person. Additional contact information offers higher engagement and a smooth, consistent experience for your audience. 

If you have your customers’ phone numbers and social media handles, you can use an omnichannel strategy to engage your audience across multiple channels. Plus, it can be useful to re-engage a customer who, for example, changed their address and forgot to resubscribe to your emails. If you have their phone number, send an SMS encouraging them to check out your latest email. Moreover, it will give them an opportunity to change their email address.

Avoid purchasing email lists

Purchased lists can contain a lot of invalid or disposable addresses, plus the existing recipients did not actively consent to receiving your marketing emails. You are not only getting a low-quality list, but also violating regulations like the GDPR, the CCPA, and the CAN-SPAM Act.

The fines for these transgressions can be pretty hefty. For example, under the CAN-SPAM Act, each separate email is subject to penalties of up to $53,088.

To avoid legal repercussions, collect emails yourself using embedded or pop-up forms and use double opt-in.

Final thoughts

Your email might not reach the subscriber for various reasons, including their email address being invalid. The most common causes are typos, deleted accounts, and the use of disposable addresses by users.

Invalid emails are a waste of marketing budget, so remove or suppress them before sending your campaign. Once your list is cleaner, create, verify, and send your campaigns with Selzy.