Disposable Email Aliases: Organize Your Messages

There is a trick you can use with many email services out there that could really save you some hassle with runaway junk email. Disposable email aliases (also known as sub-addresses) are quite handy. They allow you to quickly enter an email address in a sign-up/registration form that is different than your actual email address. Instead of signing up with your real email address (say, it’s iamawesome@somewhere.com), you would use a disposable alias instead (e.g., iamawesome+untrustworthy-service@somewhere.com).

Why Would I Ever Want to Do That?

It’s simple, really. How many times have you signed up for a new website/service, and then started receiving, even more, junk emails than you already were? Perhaps, you noticed a sudden surge in spam just after subscribing to a newsletter or entering a sweepstakes/giveaway. Many websites and services don’t hesitate to sell your information to anyone willing to pay for it.

Sure, you can enter a fake name, phone number, and even mailing address to maintain your privacy. However, you know you’ll have to verify your email address before you can gain access to whatever goodies you're after. Furthermore, you may even need to receive an email from the asking company to get what you want (e.g., newsletter, reminders, notification that you won a prize, etc.).

Providing the requesting site/service with an email alias helps you achieve your goal with them, but give more power to handle the potential onslaught of junk email. The best part is, you will receive any email sent to a disposable email alias in your regular inbox, yet you’ll be able to see that it was sent to the alias.

OK…What Can I Do with This New Power?

By providing an email alias, you can do all kinds of neat things!

• Know exactly who sold your email address.
• Easily filter incoming emails to your alias into folders/labels, instead of the standard inbox.
• Send an email directly to the trash when received to your alias.
• Register an additional account with a website/service, but still receive emails at your main one.

How Can I Create Disposable Email Addresses?

Each email provider may be different, but there are quite a few that stick to a pseudo-standard. Many email services use the plus sign (+) then whatever additional text you want after your username to construct a disposable alias. So, if I wanted to sign up to shadyplace.com, and suppose my real email address is “matt@somewhere.com”, I could instead enter: “matt+shadyplace@somewhere.com”.

Other email services use a dash/hyphen instead of a plus sign. Others still, require you to set up a dedicated “basename” to use for disposable email aliases; then you add a delimiter (dash, plus sign, or whatever), followed by your new alias.

Caveats

You knew this wouldn’t be perfect, right? Well, there are still a lot of websites/systems out there that don’t properly support valid email addresses.

Bad Validation on Web Forms

Many input forms validate the data you provide to make sure it’s properly formatted based on the type of data expected. For example, when you enter a phone number, sites may attempt to ensure you only enter digits, and only in the format allowed for the area (e.g., in the US, only 10 digits are allowed in groups, separated appropriately; ###-###-####). A US zip code must be either 5 or 9 digits and if 9, the last 4 must follow a dash (e.g., #####-####).

Well, an email address must conform to a very specific format as well. For example, an “@” must be present, but cannot be the first or last character, etc. Unfortunately, so many systems incorrectly validate email addresses. Most are overly restrictive. For example, a plus sign (+) is totally acceptable in an email address, before the “@” symbol. Yet, many websites don’t allow a plus sign at all. So, if your email provider allows disposable aliases, but requires a character that some (or many) websites won’t allow you to enter your email address, you’re out of luck with those services.

Hackable by Humans

Another issue with most disposable email aliases is the fact that it doesn’t take a genius to look for these patterns in order to thwart them. In other words, a spammer could write a program to look for the plus sign, and remove that part of the email address in order to get at your “real” address. Worse still, a nefarious programmer could substitute any text after the plus sign in order to bypass any filters you may have set up to organize/delete your incoming email.

Sending From a Disposable Email

Finally, most email providers allow you to send messages from a disposable alias. Often you can set up a standard alias (not disposable) with these services and then send from those aliases.

Support for Disposable Aliases

There are several email providers that support this concept of “disposable aliases”.

Supporting Email Providers as of 2022-Jan-17

The following email providers allow you to use disposable aliases. I’ve also provided an example alias for each, if my username (or base name) were, “groovynobody7531” (which it is not), and I wanted to create an alias for “education”.

Bonus

If you’re using the business/work edition of some of the above email providers with your own custom domain, this feature still works! For example, if you have Gmail for Business or Microsoft 365 with your custom domain (“example.com”) for email you can still use disposable email aliases (e.g., matt+whatever-i-want@example.com). I use this at work all the time when I’m testing websites we’ve written and need to set up multiple accounts to test against.