How long do you keep my data?
Google stays the authoritative source of your mail, calendar, contacts and tasks, and most of what we hold from it is a cache. A message body we fetch lives about fifteen minutes — in the memory of the process that fetched it, never written down — and then it is gone.
One thing is not a cache, and it is worth knowing about. When you ask the assistant to read or reply to an email thread, it keeps the messages of that thread as the conversation it is replying in. That conversation stays in your account for as long as the account does, the same as anything else you make here, and it is what your derived memory is built from. You can delete a single conversation in the app, and deleting your account deletes them all.
When you delete your account we remove your data from our live systems within 30 days, and residual copies age out of our encrypted backups within 90 days.
Some records are kept longer where required — for example, authentication and security audit events are retained for at least 90 days, and legal holds can extend retention where the law requires. The full schedule is in the Data Retention & Deletion Policy.
Email you send to support is the one thing account deletion does not erase. A support case — your address, your subject line, and our notes on how we handled it — is kept as readable text rather than under your account keys, because anyone can write to support, including someone with no account at all. So it is bounded by time instead: 30 days after we close the case, or 180 days from the last activity if it is still open, and then it is deleted. That includes the message in which you asked us to delete your account, if you asked by email. Asking from Account → Delete account in the app opens a case too — a person still carries the deletion out — but that one holds no address and no words of yours: your session identified you, so there is no message to keep.
See also: How do I delete my data? · How is my data secured?