Save Your ISP Email Before You Change Internet Provider

If you cancel broadband, the mailbox that came with it can go with it — sometimes within weeks, sometimes the day the account closes. This is how to save ISP email before changing internet provider, in the order that keeps every message and every login intact.

The rule that catches people: ISP mailboxes like @comcast.net, @sbcglobal.net or @btinternet.com were issued as part of a service contract, not as a standalone product. Cancel the internet plan and the address is on borrowed time. A few ISPs let you keep it if you sign in often enough. Some sell you a paid-mailbox tier after the fact. Others reclaim the address the moment your last invoice closes, and there is no undo once it is gone.

This post is a checklist you can run in an evening and finish over the following week. The order matters — copy the mail first, migrate every login off the address second, forward while the account still runs third, cancel fourth. Reversing any two of those steps is where people lose messages, get locked out of their bank, or discover a password-reset link went to a mailbox they no longer control.

Every specific ISP behaviour below is what those providers publish on their own support pages as of August 2026. Verify against your provider's live terms before you set a cancellation date — retention rules for ISP mailboxes have changed several times in the last five years and will keep changing.

What actually moves and what doesn't#

The mail itself moves. The address does not — not in any way you can rely on. Getting that split clear before you start saves a week of scrambling later.

• The mail archive moves. Every message currently sitting in the ISP mailbox can be copied to Gmail, Outlook, iCloud, Fastmail or any other IMAP host while the account is still active. This is the part you own once the copy finishes.
• The address itself usually does not. @comcast.net, @sbcglobal.net, @btinternet.com, @cox.net, @rr.com and their peers were issued as part of a broadband subscription. When the subscription ends, the ISP's terms decide what happens next, and most terms allow reclamation.
• Contacts and calendar depend on where they live. If you have been using the ISP's webmail as a contact book or calendar, export them separately — those aren't part of an IMAP mail copy. CardDAV/CalDAV or a CSV export from webmail is usually the fastest route.
• Anything sent to the old address after cancellation depends on whether a forward is still in place. Some ISPs honour an outbound forward for a grace period; others stop delivering to the address the moment service ends. Do not assume you get a bounce message that tells the sender to try again — a silent drop is common.
• Two-factor codes and password-reset links tied to the old address stop being usable the same day the mailbox stops being usable. Migrate every login off the address before the mailbox goes dark, not after.

How long does an ISP keep your email after you cancel?#

There is no single answer, and this is where reading your specific ISP's terms pays off. Behaviour clusters into three patterns.

Some providers let you keep the mailbox if you sign in periodically. Xfinity/Comcast's own support page describes an inactivity policy for @comcast.net after service cancellation — sign in through the Xfinity webmail regularly and the address stays alive; go quiet and it is disabled. The exact interval has changed over the years, so check the current terms before relying on it.

Some sell you a paid retention tier. BT in the UK moves former customers onto BT Premium Mail, a paid subscription to keep the @btinternet.com or @btconnect.com address. If you do not opt in during the grace window, the address is deleted.

Some end the address at cancellation. Several US and UK ISPs have simply retired their consumer mail service in the last few years — Verizon handed its domain off years ago, Sky UK shut down Sky Yahoo Mail, TalkTalk retired its mailboxes for many customers. If your provider has done this, your grace period is whatever they announced, and it does not restart.

The safe assumption for planning is the third one. Copy everything, migrate every login, and treat any grace period you happen to get as insurance rather than a plan.

Pre-migration checklist#

Run this list before you touch the cancellation form. Nothing here requires you to have chosen a new ISP yet.

• Pick a destination inbox. Gmail, Outlook.com, iCloud Mail, Fastmail and Proton all accept an incoming IMAP transfer from an ISP mailbox. Choose the one you actually want to live in for the next five years — the point of this move is not to do it again in six months.
• Confirm IMAP is enabled on the ISP side. Most consumer ISP mailboxes support IMAP, but a few default to POP3 and require flipping a setting in webmail. Check the ISP's help pages for the current IMAP hostname, port and authentication method.
• Find your app password if the ISP requires one. Some ISPs no longer let a third-party client sign in with the account password directly — you generate a per-app password inside webmail settings. This is what Gmail's own import-mail flow expects.
• Inventory every service that emails you at the old address — bank, tax office, doctor, utility, subscription, government, employer. Search your inbox for the phrase "do not reply" and for password-reset messages; both surface the accounts you have forgotten about.
• Enable a forward from the ISP mailbox to the new address while the account is still active. Even a temporary forward gives you a safety net during the login migration.
• Set a cancellation date with real margin — at least two weeks after you plan to finish the login migration, not the same afternoon. Cancelling the same day you flip your bank login off the old address is where recoverable mistakes turn into unrecoverable ones.

How do I copy mail out of an ISP mailbox?#

1. 1

   Turn on IMAP on the ISP mailbox and generate an app password

   In the ISP's webmail settings, enable IMAP access if it isn't already on, and generate an app-specific password if the provider requires one. Note the IMAP hostname, port (usually 993 with SSL/TLS) and the exact username format — some ISPs want the full address, some want the local part only.

2. 2

   Choose the destination inbox and enable its import path

   In Gmail, this is Settings > Accounts and Import > Check mail from other accounts, which per Gmail's own help page uses POP3 to pull messages in. To copy folders and preserve structure, use an IMAP-to-IMAP transfer tool (Thunderbird, imapsync, or the destination host's own migration import) rather than Gmail's built-in POP importer.

3. 3

   Run a first small transfer against one folder

   Pilot with a single folder — Sent, or a small archive folder — before you point the tool at the whole mailbox. This surfaces authentication issues, throttling by the ISP, and any folder-naming quirks (some ISPs use non-standard names for Sent/Drafts/Trash) before you commit to a multi-hour full transfer.

4. 4

   Transfer the full mailbox

   Run the full copy. Expect ISP-side rate limits — most consumer providers cap concurrent IMAP connections, so a large mailbox can take several hours. Leave the tool running and re-check completion the next day rather than watching a progress bar.

5. 5

   Verify counts before you move on

   For every folder, compare message counts between the ISP mailbox and the destination. Off-by-a-few is normal (drafts, deleted items in Trash), off-by-hundreds is not. Rerun the transfer for any folder that came up short before you touch the login migration in the next step.

6. 6

   Change every login off the ISP address

   Go through the inventory from the checklist. In each service's account settings, update the primary email to the new address, then request a verification message and confirm it. Do the highest-stakes accounts first — bank, tax, government, primary work login, password manager — while both mailboxes still work, so you can receive the verification either way.

7. 7

   Set a forward and a helpful auto-reply

   Configure the ISP mailbox to forward to the new address for anything you missed. Add an auto-reply that names the new address so senders can update their own records. Keep both running until you cancel the service.

8. 8

   Cancel the internet service

   Only after the mail is copied, verified, every login is migrated and both a forward and an auto-reply are in place. Confirm in writing what the ISP will do with the mailbox and the forward once service ends — some send a final confirmation with the exact deactivation date, which is worth keeping.

What breaks — and how to keep each thing intact#

Almost everything on this table is silent when it breaks. Mail does not bounce, a login does not warn you, a forward stops working without a notice. Treat every row as something to verify, not something to trust.

Where the migration usually goes wrong#

The two mistakes that turn a clean move into a scramble are cancelling before the login migration is complete, and trusting that the ISP will honour a forward for longer than they actually will. Both are avoidable, and both are more common than the mechanical failures in the transfer itself.

The third is finishing the technical steps and forgetting to tell anyone the address changed. A checklist that copies every message and updates every login but never sends a short note to the people who email you weekly leaves them mailing an address that is about to disappear.

Rollback plan#

Rollback is possible right up until the day the ISP deactivates the mailbox, and impossible afterwards. That is why every step above is non-destructive on the ISP side — copying mail out does not delete it, generating an app password does not lock you out of webmail, changing a login on one service does not touch any other service.

If something goes wrong mid-migration, revert the login change on that specific account back to the ISP address, confirm mail still reaches it, and try again once the underlying issue is fixed. As long as the mailbox is still active, no single mistake is fatal.

The one place rollback does get harder is the DNS/forwarding sense — once you have told a few hundred senders about the new address, you cannot unsay it. That is fine. The new address is where you are going regardless.

The hard limit is the ISP's own deactivation date. After that day, there is no console to log into, no support ticket that recovers the address, no way to retrieve mail that arrived while the forward was in place but never got delivered. Every hour of margin you build in before cancellation is worth it.

Doing it without downtime#

A one-day cutover is where the breakage in the table above shows up. Staggering the move over two or three weekends keeps the ISP mailbox as a live safety net while every high-stakes login is verified on the new address.

• Weekend one: copy the mail and pilot the destination inbox. Verify folder counts. Do not touch a single login yet.
• Weekdays: use the destination inbox as the primary. Forward the old address to it. This is the confidence-building phase — every day both inboxes stay in sync is a day you know the copy worked.
• Weekend two: migrate the highest-stakes logins — bank, government, employer, password manager, primary shopping accounts. Verify each with a fresh password-reset test.
• Following weekdays: work through the long tail — newsletters, receipts, low-frequency accounts. This is the part that never really ends; be at 90% before cancellation and mop up the rest via the forward.
• Weekend three: set the auto-reply and confirm the cancellation date. Cancel the service. Verify one last time that the forward is still delivering during whatever grace window the ISP allows.

Where AI Emaily fits#

This checklist gets the mail out of the old ISP mailbox and every login onto a new address. What it does not do is answer the second question that appears the day the copy finishes: which client you actually read that mail in.

We build AI Emaily, an AI-native email client that connects to Gmail, Outlook, iCloud and any IMAP host — including the destination you just migrated to — with approve-before-send on every reply the agent drafts, a full audit trail on every action it takes, and no model training on your mail. There is no permanent free tier: it is a 7-day trial on Pro or Autopilot, card required, $0 if you cancel before day 7. The homepage at / describes the shape and /pricing has the current numbers. AI Emaily does not touch the ISP-to-new-host copy above — you still run that yourself — but once the mail lands, connecting a client is standard OAuth or IMAP setup, not a second migration project.