Inbox lifecycle
The Last Hour of a Temporary Inbox
A MailOnce inbox is built around a deadline. The useful question is not only how long it lasts, but what you should do while the clock is still moving — and what changes when it reaches zero.
00:60 · The inbox begins
You have an active address, not permanent storage
MailOnce assigns the inbox an expiry when it is created. The configured default initial lifetime is one hour, but the countdown shown for the current inbox is the clock that matters. During that active window, keep the address available for the task that caused you to create it.
A temporary inbox works best when the task has an ending: receive the code, open the expected message, finish the signup, collect the information you need, then leave. Do not treat the timer as a decoration or the inbox as a place to archive something you may need months later.
The middle of the clock
Nothing special happens just because time is passing
The remaining time tells you how long normal access to that inbox is expected to continue. Messages can arrive throughout the active lifetime. If you are waiting for a sender, the important comparison is simple: does the task still have enough time to finish before the inbox deadline?
If the message is merely delayed, keep the same address. Changing it does not move an email that was already sent to the old one, and a website waiting to verify the original address will not automatically follow you to a new inbox.
KEEP THE ADDRESS
Extend when the unfinished task still belongs to this inbox
Near expiry, an active session may become eligible for Extend Inbox. In the current MailOnce rules, the extension window is when more than zero and no more than 15 minutes remain. A successful extension resets expiry to 60 minutes from the backend extension time, and an inbox has up to three successful extensions.
Use that extra time when the same address is already tied to a pending verification or message. The rules above are the Extend Inbox rules: eligibility begins only while the inbox is still active and within the final 15 minutes, each successful extension resets the active window to 60 minutes from the backend extension time, and the current limit is three successful extensions.
LEAVE THE ADDRESS
Change when you are actually finished with the current inbox
Changing your temporary email starts a different address. It is the right move for a new task, not a substitute for giving the current task more time. If a code, link or reply is still expected at the old address, finish that flow before moving on.
00:00 · Expired
Zero is a boundary, not a warning
When the active deadline has passed, normal ownership checks no longer treat the inbox as active. An extension requested at or after expiry cannot revive it. For practical use, treat the session as finished rather than as a mailbox you can depend on reopening later.
That is also why an expiring address is a poor foundation for an account that may need password recovery, ownership checks or future verification. The address served a temporary task; it was not a promise of permanent access.
What about messages after expiry?
Active access ending and stored data being physically removed are different lifecycle events. Expiry closes normal inbox access; later cleanup follows separate eligibility and execution rules. That technical distinction should never be treated as a recovery window or a reason to leave important information behind.
In other words: data may have a cleanup lifecycle after the access deadline, but the user-facing promise is still temporary access. Plan as if anything you need must be handled before the clock reaches zero.
Can the same expired inbox be reopened?
Do not build a workflow around reopening an expired temporary inbox. Once active access ends, the safe operational assumption is that the session is over. If a service will need to contact you again later, use an email address designed to remain under your control.
The whole lifecycle in one sentence
Create for a short task → watch the real deadline → extend only if the same task needs more time → finish before zero → treat expiry as the end.
Ready for the next task?
Start clean instead of carrying an expired inbox forward
When the task tied to this address is complete, the simplest next step is a fresh temporary inbox. You get a new active address and a new countdown without depending on an expired session.
Create a new temporary email →Continue through the Knowledge Center
The inbox expired. What should you understand next?
Follow the part of the workflow that matters to you now: what happens to stored data, what expiry means for verification, or when a new address is the better choice.
After expiry
Privacy & Data Lifecycle
See the difference between losing inbox access, retention boundaries, purge eligibility and physical cleanup.
Follow the data →Pending verification
OTP & Verification
Understand code expiry, resends and why adding time to an inbox does not extend the sender's OTP validity.
Understand verification →New task
Create Temporary Email
Learn when to keep the current address, when to change it and how to start the next temporary inbox cleanly.
Start with the right address →