How to Switch an Outlook Account From POP3 to IMAP Without Losing Emails

Many people set up Outlook years ago with POP3 and never changed it. POP3 worked fine on a single computer, but it struggles today when you also want mail on your phone, tablet, and webmail, all showing the same folders. Switching to IMAP solves that, yet the fear of losing old emails stops many people from trying.

The good news is that you can switch safely if you follow the right order. You cannot simply change a POP3 account to IMAP inside Outlook with one setting — you need to add a new IMAP account, move your old mail across, and only then remove the old account. This guide walks you through each step carefully.

Quick Answer

Back up your POP3 mail to a PST file first, then add the same address as a new IMAP account in Outlook. Copy or move your old folders and messages into the IMAP account, let everything sync to the server, check the mail on webmail, and only then remove the old POP3 account. Never delete the POP3 account before your old emails are safely copied and verified.

POP3 and IMAP: What Changes When You Switch?

With POP3, Outlook downloads messages from the server to your computer. In many older setups, the server copy is then deleted. Your real mailbox lives mainly inside Outlook on that one PC, often in a PST file. Folders you created in Outlook may exist nowhere else.

With IMAP, the mailbox lives on the server. Outlook, your phone, and webmail all show the same messages and folders because they are looking at the same server mailbox. If you read, move, or delete a message on one device, the change appears everywhere.

That difference is exactly why a direct conversion is not possible. Outlook treats POP3 and IMAP accounts as different account types with different storage. The safe path is to run both side by side briefly, transfer the mail, and then retire the POP3 version.

Before You Start: Preparation Checklist

• Find your provider’s IMAP server, port, and security settings. You will need them if automatic setup fails.
• Make sure you know your current email password. Test it by logging in to webmail.
• Check how much mail you have. A very large mailbox can take hours to upload during the move.
• Confirm your provider gives enough server storage for all the mail you plan to move.
• Do the switch when you have stable internet and time to let syncing finish. Do not rush it.

If you are unsure of your server details, our walkthrough on how to find your email provider’s exact IMAP server and port settings shows where to look them up for any provider before you begin.

Step 1: Back Up Your Existing POP3 Mail

This step is your safety net. Do not skip it.

1. In classic Outlook, click File, then Open and Export, then Import/Export.
2. Choose Export to a file, then Outlook Data File (.pst).
3. Select your POP3 account or the folders you want to keep, including Inbox, Sent Items, and any personal folders.
4. Tick Include subfolders, choose a save location you will remember, and finish the export.
5. Confirm the PST file exists and has a sensible size.

Store a copy of this backup somewhere separate, such as an external drive or cloud storage. If anything goes wrong later, this file contains your old mail and you can import it again. Microsoft documents this process in its official guide to exporting Outlook items to a PST file.

Step 2: Stop the POP3 Account Downloading New Mail

Before adding the IMAP account, prevent confusion between the two accounts. Both accounts will try to receive mail for the same address during the switch.

In Account Settings, you can leave the POP3 account in place but avoid sending and receiving with it, or simply be aware that new messages may arrive in both accounts until the move is done. Do not delete anything yet. The POP3 account is still the home of your old mail at this stage.

Step 3: Add the Same Address as a New IMAP Account

1. Click File, then Add Account.
2. Enter the same email address and click Connect.
3. If Outlook offers account type choices, select IMAP. Enter your password when asked.
4. If automatic setup fails, use Manual setup and enter your provider’s IMAP server, port 993 with SSL/TLS in most cases, and the matching SMTP settings for sending.
5. Finish the setup and let Outlook create the new account in the folder pane.

You will now see two accounts with the same address: the old POP3 one and the new IMAP one. Give them clear display names in Account Settings if Outlook allows it, such as Old POP3 and New IMAP, so you do not move mail in the wrong direction.

Step 4: Move Your Old Emails Into the IMAP Account

Now transfer your history. Work folder by folder, in small batches, especially with large mailboxes.

1. Expand the old POP3 account and open its Inbox.
2. Select a batch of messages. You can select a range with Shift and click.
3. Drag them into the Inbox of the new IMAP account, or right-click, choose Move, then Copy to Folder, and pick the IMAP folder. Copy is safer than Move for the first batches.
4. Repeat for Sent Items, Drafts, and each personal folder. If you had custom folders under POP3, create matching folders in the IMAP account first, then copy into them.
5. Watch the sync progress in Outlook’s status bar. Let each batch finish uploading before starting a huge one.

Contacts and calendar items stored locally may need separate handling. Export them or check whether they live in the PST file. Email moving alone does not always carry contacts across, depending on your setup.

Large attachments slow uploads down. If a batch seems stuck, wait. Uploading several years of mail to a server is normal to take a long time, particularly on slow connections.

Step 5: Verify Everything Arrived Safely

1. Compare message counts or spot-check important folders in both accounts.
2. Log in to your provider’s webmail. Your copied folders and messages should appear there, because webmail shows the server mailbox directly.
3. Open a few old messages, including ones with attachments, to confirm they load properly.
4. Send and receive a test email using the new IMAP account.

Only move to the final step when webmail shows your mail. That is the proof that the messages are truly on the server and not just visible inside Outlook.

Step 6: Remove the Old POP3 Account

1. Click File, Account Settings, Account Settings.
2. Select the old POP3 account.
3. Click Remove and confirm.

Removing the account from Outlook does not delete your PST backup file. Keep that backup for at least a few weeks after the switch, until you are completely confident the IMAP mailbox is complete. Set the IMAP account as the default account if Outlook asks.

Common Mistakes to Avoid

• Deleting the POP3 account first: This is the number one way people lose mail. The old account may be the only place those messages exist.
• Trying to edit POP3 settings into IMAP settings: Outlook does not convert account types in place. Add a new account instead.
• Moving everything at once: Huge drag-and-drop moves can fail or freeze. Small batches are slower but far safer.
• Not checking webmail: If it is not on webmail, it is not fully synced to the server yet.
• Throwing away the PST backup too soon: Keep it until the new setup has worked well for several weeks.
• Forgetting contacts and rules: Check contacts, signatures, and message rules after the switch, as they may belong to the old profile setup.

Conclusion

Switching an Outlook account from POP3 to IMAP without losing old emails is very doable when you respect the order: back up first, add the new IMAP account alongside the old one, copy your folders across in batches, verify on webmail, and only then remove POP3. Take your time with the copying stage and keep your PST backup safe. Once finished, your mail will sync properly across Outlook, your phone, and webmail, and you will never need to wonder which computer holds the real copy again.

Frequently Asked Questions

Can I change my POP3 account to IMAP by editing its settings?

No. Outlook does not let you convert an existing POP3 account into an IMAP account in place. You must add a new IMAP account for the same address, move your mail, and then remove the old POP3 account.

How long does the switch usually take?

The setup itself takes minutes, but copying old mail depends on mailbox size and internet speed. A small mailbox may finish in under an hour. Several gigabytes of mail can take many hours to upload and sync.

Will my folders move to IMAP as well?

Yes, if you create matching folders in the IMAP account and copy the messages into them. Folder contents do not move automatically, which is why the manual copy step in this guide is essential.

What happens to new emails during the switch?

They may arrive in one or both accounts while both exist. That is temporary and harmless. After you remove the POP3 account, all new mail arrives only in the IMAP account and syncs everywhere.

My provider’s storage is too small for all my old mail. What can I do?

Keep older mail in your PST backup as an archive and move only recent years to IMAP. You can open the PST in Outlook whenever you need the archive, while daily mail enjoys full IMAP syncing.