What changes when you block or delete a mask
A Fastmail masked address is a forwarding address, not the account it protects. Changing its status in Settings does not log you out of any account that has it on file. What changes is whether mail sent to that address reaches your inbox, lands in Trash, or is refused outright.
Fastmail masked addresses can be managed in Settings under Masked Email; Active accepts messages, Blocked sends them to Trash, and Deleted bounces them. Source
The practical risk is not the mask itself. It is a password-reset or security-alert email that arrives after you have stopped reading that address. If the mask is the only recovery route on a known account, a Blocked or Deleted status can quietly remove your way back in.
Step 1: Map the dependencies before you touch the status
Open Settings and then Masked Email, and read the description field for the address in question. Fastmail lets you attach a note to a mask; if the note names the service, that is your starting list. If it is blank, reconstruct the list from your own records rather than guessing.
For each account you believe uses the mask, record:
- The service and the login email shown in its account settings.
- Whether the mask is the primary email or a backup contact.
- Whether password reset, two-factor codes or security alerts are sent there.
- Any other recovery method already attached, such as a phone number, authenticator app or a second email you still control.
| Question | Why it matters |
|---|---|
| Is this mask the only route to reset the password? | If yes, blocking or deleting it can lock you out |
| Does the service send login codes here? | Codes may stop arriving or be refused |
| Is there a second recovery email or phone? | This is the replacement route you need |
| Is the mask also used for billing or legal notices? | Those messages may matter even if you rarely log in |
This mapping is a proposed reader checklist, not something we performed or tested. Treat it as a worksheet you fill in from your own accounts.
Step 2: Choose Active, Blocked or Deleted deliberately
Fastmail gives three states, and they behave differently.
- Active accepts messages and delivers them normally.
- Blocked sends messages to Trash instead of your inbox.
- Deleted bounces messages back to the sender.
Blocked is a middle option: mail is not delivered to your inbox, but it is not refused either. Deleted is the stronger signal, because senders receive a bounce. Neither state removes the address from an account that already has it stored, so the account will keep trying to use it until you change the address on that account.
Deleted masked addresses can be restored; an address that has never received mail can instead be permanently deleted. Source
That reversibility is the reason to act in stages. If you are unsure whether a mask is still in use, Blocked lets you stop seeing routine mail while keeping the address recoverable. Move to Deleted only when you have confirmed nothing depends on it.
Step 3: Record a replacement recovery route first
Before you retire the address, set up and confirm a recovery method you control on each dependent account. That means logging in, opening the account’s security or contact settings, and adding a second email or phone that you can access. Confirm it works by completing any verification step the service offers.
Keep that recovery method in place until the account itself is closed or the address is fully changed everywhere. Do not remove your own recovery options in advance of finishing the change. An edited profile or an empty inbox on the masked address does not prove that the service has dropped the address from its records.
If you cannot access the account to change its email, do not delete the mask. Leave it Active or Blocked and recover access through the service’s own support process first.
Step 4: Check Trash and Spam when you search
A common failure path is searching your mailbox for the masked address, finding nothing, and concluding the mask is unused. That conclusion can be wrong.
Searching mail for a masked address may omit Trash and Spam unless the search includes those locations. Source
When you audit, search each relevant location explicitly, including Trash and Spam. Mail routed there by a Blocked status will not appear in a default search. If you see recent messages from a service you thought was dormant, that is a dependency to resolve before deleting the mask.
A red flag that is not proof
Receiving mail at a masked address does not by itself show that a seller leaked your data. Addresses can be shared, guessed, resold as part of a list, or reached through a service you signed up for directly. Use the message content and the sender’s own account records to judge, and treat a single unexpected email as a prompt to check the account, not as a conclusion about any company.
Where TraceSeek fits, and where it does not
TraceSeek is a separate app for searching publicly accessible profile candidates from a supplied username, across 3,000+ platforms. It cannot change Fastmail masked-email settings, recover a private account or verify anyone’s identity. If your concern is a public profile rather than a mailbox setting, that is a different task from the one on this page.
If you are handling a similar pause-or-retire decision on another masking service, you can review the related account task to compare the steps.
When to stop
Pause the change if any of these is true:
- You cannot log in to an account that uses the mask.
- The mask is the only recovery route and no replacement is confirmed.
- You have not yet checked Trash and Spam for recent mail.
- You are unsure whether the address is shared with another person or service.
In each case, keep the mask Active or Blocked, resolve the gap, and only then consider Deleted.