How to: Using Gmail's "+" addresses

I wrote this for my partner (but thought it might be useful to other folx too).

She’d come to me with two seemingly unrelated problems.

First, she wanted to corral certain emails—notifications from a few of the apps she runs for her business—out of her inbox and into their own folders, automatically, without having to triage them by hand.

Second, between us we needed to test the sign-up flow on a promotion we were running, which meant conjuring up a handful of mock “new” users, to test the process under different conditions.

I worked out that both of those are pretyt much textbook cases for the same trick: the Gmail ”+” address. I tried to explain it verbally to her, and failed 😏 So I wrote down an explanation—including the difference between that trick and a “real” alias, because the two can be a lil’ confusing, and the distinction matters once you start relying on them for things like delegation etc.

So, here’s the guide I ended up writing. It’s aimed at anyone new to managing email addresses in Gmail or Google Workspace. Hope it’s helpful to someone.

The ”+” trick

Add a + and any text after your username, before the @. Mail still lands in your normal inbox.

An example, assuming that your main username/mailbox name is “alice” (yes, if you’re in Australia, I can hear the chant already):

alice+shopping@yourdomain.com  →  alice@yourdomain.com
alice+netflix@yourdomain.com   →  alice@yourdomain.com

These all just end up in your standard mailbox. You don’t have to do anything to set these up within Google Workspace—you invent them on the spot, as many as you like. Google ignores everything between the + and the @ in terms of mailbox routing. But you can reference those in other ways, once the email is in your inbox.

What they’re good for

• Filtering: build rules on the tagged address (e.g. auto-label anything to alice+receipts@, or bypass your inbox into a sub-folder, marking it as important or starring it automatically, etc.)
• Tracking leaks: give each signup its own tag. If spam starts arriving at alice+somestore@, you know who sold your address. (Although this is pretty weak—as you’ll see later.)
• Testing systems: let’s say you want to test a “new signup” form on your website. You can use alice+test20260620.1@ to register a new user, and the mail will still be sent and received in your inbox. As there’s no formal “email address” to set up, you can just delete the user from your test system later—nothing more to do in Google Workspace.

Official aliases

An alias is a real, pre-registered address that you or an admin explicitly configure in the Google Workspace admin console, or your user profile. Example: your main mailbox is amara@yourdomain.com, and you add amara.okonkwo@ or support@ as an alias. Both deliver to the same inbox, but support@ is a genuinely separate address—not a tagged version of amara@—so you can route it to a different mailbox later, should you choose.

How they differ

1. Ephemeral vs. permanent

”+” tags are ephemeral: you make them up as needed and throw them away; nothing is registered anywhere.

Aliases are more permanent and provisioned: they exist as configured addresses until someone removes them.

2. They look different

Spammers can trivially strip +shopping to recover your base address. An alias like support@ reveals nothing about your personal address or the underlying mailbox setup you have.

3. Quantity

”+” variations are unlimited. Aliases are finite (Workspace caps them per user).

4. Delegation—the important one

A ”+” tag can only ever land in the same inbox as the base address. There’s no way to send kenji+sales@ somewhere else (other than forwarding). If you ever want an address to be handled by a different mailbox later—say, sales@ should go to a shared inbox or a teammate—you must use a real alias (or a group). Aliases can be reassigned or pointed elsewhere; ”+” tags cannot.

Rule of thumb