There’s a simple way to tell if your mailbox has the useful plus + address feature. Plus email addressing (aka disposable or sub-address) is sometimes available automatically (Gmail or Outlook.com) or has to be switched on (Microsoft 365 hosting).
Some other mail hosts might have an option to allow plus + addresses for your mailbox.
What are email Plus addresses and how to use them explains how handy + addressing is.
You can search your mailbox host support or just web search for your mailhost name with ‘plus email address’.
Or better and faster, just try a test Plus address email (me+test@mydomain) and see what happens.
Send a test + email
If you think your mailbox has plus addressing, test it before handing out plus addresses to other people. Just to make sure it’s all working as expected.
From a different mailbox, send a message to yourself with a plus address extra e.g.
peter+test@ . If that message arrives OK, then you’re good to go.
If it’s not setup, the message should ‘bounce’ with an ‘unknown user’ type error.
No need to test each plus address you use … just a starting ‘one off’ test.
Gmail has another address variation
Yahoo doesn’t have plus + address but do have a form of ‘disposable’ email address.
These separate addresses use a hyphen – separator AND have to be individually setup in advance.
See Yahoo mail for details.
How to get ‘Plus’ email addresses, the new feature in Microsoft 365 and Outlook.com
What are email Plus addresses and how to use them
Get the most from Plus addresses in Outlook
What can you put in your email address?