How to Check Where a Plus Address (name+tag@) Is Delivered
A plus address such as jane+shop@gmail.com is delivered to jane@gmail.com when the provider supports plus addressing. Enter it in the plus address checker to see the base mailbox, the tag, whether the provider documents the feature, and the form to use when removing duplicate sign-ups. For company domains, only the domain's MX records are looked up to find the provider; nothing is sent.
Step 1: enter the address
Type one address that contains a +. The tool splits it into the base mailbox (before the +), the tag (after it) and the domain.
Step 2: see what the provider does
Providers differ, and the tool says what each one documents:
| Provider | Plus addressing |
|---|---|
| Gmail and Google Workspace | Documented |
| Microsoft 365 | Documented, on by default for business mailboxes |
| Proton, Fastmail | Documented |
| Outlook.com, Hotmail | Not documented by Microsoft |
| Anything else | Not traced; the tool says so |
By hand: take the part before the + as the base mailbox, and confirm the provider's help page supports it. For Gmail, dots are ignored too; see Gmail dots and plus addresses.
Step 3: use the dedupe key
The dedupe key is the base address, normalised for the provider. jane+trial7@gmail.com and jane@gmail.com reach the same person. For trial abuse, see plus addressing and trial abuse. To merge duplicates in a list, use remove duplicate emails or the Gmail address normalizer.
A plus address is not a fake address
It reaches a real inbox. That is why a verifier treats the base mailbox as the thing to check. If the base address is valid, the tagged one is delivered, provided the domain has not switched plus addressing off.
What this check cannot do
- It cannot tell whether the mailbox exists or whether the domain's admin turned plus addressing off.
- Only + is treated as a tag. Providers that use another character, or separate alias addresses, are not traced back.
- Support is taken from each provider's own documentation; where there is none, it says so.
Check the rest of the list
A plus address is one row. Check the list it came from on the verify page: the first 100 email checks are free with a Google sign-in, no card. Each address comes back valid, risky or invalid with a reason such as "Mailbox exists" or "Mailbox not found". See bulk email verification and pricing.
Check a plus address now
Paste it into the plus address checker.
Common questions
What does a plus sign in an email address mean?
Everything after the + is a tag. If the provider supports plus addressing, mail goes to the address without it. Gmail, Google Workspace and Microsoft 365 document it.
Does Outlook support plus addressing?
Microsoft 365 business mailboxes do, on by default. Microsoft does not document it for consumer Outlook.com and Hotmail addresses.
Is a plus address a fake email?
No. It reaches a real inbox. It can signal someone signing up more than once, so dedupe it against the base address.
Is anything sent to the address?
No. For company domains only the domain's MX records are looked up; the mailbox is never contacted.
Can the tool tell if the mailbox exists?
No. It reads the address and the domain's MX. Whether the mailbox exists, or the admin turned plus addressing off, needs a mailbox check.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.