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How it works

Your new mailbox is four clear steps away.

01
≈ 30 seconds

Connect

Enter the IMAP servers, mailbox logins and app passwords. The port fills itself in: 993 for SSL/TLS, 143 for STARTTLS.

02
≈ 1 minute

Check

We test TLS and authentication separately, then measure the full size of the mailbox. If something fails, the error says which part — the certificate or the password.

03
an hour to a day

Run it

A mailbox up to 5 GB transfers for free. Above that you pick a plan first. Running it again copies only the messages that are missing.

04
≈ 5 minutes

Compare

You get a report — compare the folders before deleting or shutting down the old mailbox. We never delete the source mailbox, under any scenario.

Protocol boundaries

What moves with the mail, and what you have to move by hand.

IMAP is a protocol about messages and folders, and only about those. Everything else lives outside it, and it is fairer to say so before the transfer than to field the question after.

Transfers

In full, byte for byte, with no repacking

  • Whole messagesThe original RFC 822 object: headers, body, every attachment
  • Received datesMailbox order stays intact — nothing turns up dated today
  • FlagsSeen, answered, flagged, draft
  • Folder structureNesting of any depth, non-ASCII names in UTF-7
  • Sent and DraftsOrdinary IMAP folders — they move like the inbox does

Does not transfer

This is not IMAP — the data sits in other systems at the provider

  • Contacts and calendarsThey live in CardDAV and CalDAV — export them separately, as vCard and ICS
  • Filters and rulesSieve or Outlook rules — recreate them by hand in the new mailbox
  • Auto-reply and signaturesWebmail settings, nothing to do with the messages themselves
  • Aliases and forwardingDomain configuration — it moves along with DNS and MX
  • In-Place Archive at MicrosoftA separate store, not visible over IMAP at all

What to do about it: export contacts and the calendar from the old webmail to vCard and ICS before the mailbox is shut off — it takes five minutes, but only while you still have access. Filters are easier to write from scratch: over the years you usually collect more of them than you need.

Popular routes

Clear guides for the moves people make.

Pick a ready-made route — “move from … to …” — or connect any two compatible IMAP servers by hand.

GmailOutlookGuideOutlookGmailGuideYahoo MailGmailGuideiCloud MailGmailGuidecPanelMicrosoft 365GuideYandexZohoGuideOld hostNew hostGuideAnyAnyManual

All routes

A detailed walkthrough for every pair

Hosts, ports, app passwords and what breaks on this particular pair — one page per route.

Gmail → OutlookMigrate email from Gmail to OutlookMove messages, folders and attachments from Gmail to Outlook.com over IMAP. App passwords, the All Mail trap and the 2.5 GB daily cap, explained.Outlook → GmailMigrate email from Outlook to GmailMove Outlook.com email into Gmail over IMAP with dates, flags and nested folders intact. Microsoft app passwords and the Junk vs Spam mismatch covered.Gmail → Microsoft 365Migrate Google Workspace to Microsoft 365Migrate corporate mail from Google Workspace to Microsoft 365 over IMAP. Basic auth is disabled, so OAuth 2.0 and tenant admin consent are required.Microsoft 365 → GmailMigrate email from Microsoft 365 to GmailMove corporate mail from Microsoft 365 to Google Workspace over IMAP. Source-side OAuth, Exchange throttling and Google storage quota, covered.Яндекс → GmailMigrate email from Yandex Mail to GmailMove email from Yandex Mail to Gmail over IMAP. Yandex ID app passwords, enabling IMAP access and the rate limiting that breaks fast transfers.Mail.ru → ЯндексMigrate email from Mail.ru to Yandex MailMove email from Mail.ru to Yandex Mail over IMAP. App passwords are required on both sides and the two services expect different login formats.iCloud → GmailMigrate email from iCloud to GmailMove iCloud Mail to Gmail over IMAP. Apple always requires an app-specific password, and the login is the part before the @ only.Yahoo → GmailMigrate email from Yahoo Mail to GmailMove Yahoo Mail to Gmail over IMAP. Yahoo app passwords, the Bulk Mail folder instead of Spam, and nested folders preserved as they are.cPanel → Microsoft 365Migrate email from cPanel to Microsoft 365Move mail from cPanel hosting to Microsoft 365 over IMAP. Self-signed certificates, connecting by IP address and the right MX cutover order.cPanel → cPanelMigrate email from one hosting provider to anotherHow to move mail when changing hosting without losing messages. Connecting by IP, MX cutover order, TTL, and the second pass afterwards.Яндекс → Microsoft 365Migrate email from Yandex 360 to Microsoft 365Corporate mail migration from Yandex 360 to Microsoft 365 over IMAP. Source-side app passwords and Microsoft OAuth admin consent explained.cPanel → GmailMigrate email from cPanel to GmailMove mail from cPanel hosting into Gmail or Google Workspace over IMAP. Shared-host certificates, connecting by IP, and shared Google quota.Zoho → Microsoft 365Migrate email from Zoho Mail to Microsoft 365Move Zoho Mail to Microsoft 365 over IMAP. Zoho regional data centres, app passwords and Microsoft OAuth consent, all in one guide.Exchange → WorkspaceMigrate Exchange Server to Google WorkspaceMove mail from on-premise Exchange Server to Google Workspace over IMAP. Enabling IMAP4, certificates, and what the protocol cannot carry.Gmail → ЯндексMigrate email from Gmail to Yandex MailMove Gmail messages to Yandex Mail over IMAP. The All Mail duplication trap, app passwords on both sides and each provider’s rate limits.Gmail → ZohoMigrate email from Gmail to Zoho MailMove Gmail to Zoho Mail over IMAP. A common route when leaving paid Google Workspace: Zoho regional hosts and the All Mail duplication trap.

Find out how big your mailbox is. It costs nothing.

Connect two servers, look at the size and decide. Or take the client and keep everything on your side.

Start the transferDownload for Windows
Code on GitHub · built on imapsync · no sign-up