imap-migrate

Overview

imap-migrate is a free, open-source command-line utility for transferring email between IMAP accounts. It is best suited to people comfortable with Python who need to move a folder without losing message dates and flags. Its narrow scope makes it a practical migration aid, not a complete mailbox-rebuilding solution.

Key features

Messages retain their original received dates and flags such as Seen and Flagged, which helps preserve useful context after a move. Progress reporting shows speed, successful and failed counts, and estimated time remaining; actions are also recorded in migration.log. That makes it easier to monitor a run and investigate errors, though it does not broaden the tool beyond a single folder transfer.

The --dry-run option checks the connection and settings without moving mail. Interrupted migrations can be rerun without creating duplicate emails, a meaningful safeguard when a transfer is disrupted. Credentials work as command-line arguments or environment variables; the project recommends environment variables as the more secure approach, but makes no certification or compliance claims.

IMAP access must be enabled on both accounts, and the tool requires Python 3.12 or later. The recommended dependency manager is uv. These requirements are manageable for command-line users, but add setup work for anyone seeking a ready-to-run desktop app.

Migration covers the contents of one folder into another. It does not rebuild a full folder tree or carry provider-specific features such as Gmail labels and categories, so it is a poor fit for preserving a complex mailbox exactly as organized.

Pricing

The Free plan costs nothing and includes IMAP folder migration, with Python 3.12 or higher and IMAP access on both accounts required. There are no paid tiers or usage quotas to compare, but the free tool's practical limit is its one-folder scope and lack of provider-specific feature migration.

Platforms

imap-migrate supports Linux, macOS, and Windows. It is a command-line tool rather than a graphical email client, so platform support does not remove the need to work with Python and account settings.

Who it's for

Choose imap-migrate for a no-cost, focused transfer between IMAP-accessible accounts when preserving dates and flags matters and command-line setup is acceptable. It is less appropriate for users who need to recreate nested folders, retain Gmail labels or categories, or avoid Python requirements.

Pros and cons

• Pros: Free and open-source under the MIT License, with no paid tier to unlock folder migration.
• Pros: Preserves received dates and flags, and reports progress, errors, and estimated remaining time.
• Pros: Dry runs check settings before transfer, and reruns after interruption avoid duplicate emails.
• Cons: Requires Python 3.12 or higher and IMAP access enabled on both accounts.
• Cons: Transfers one folder's contents rather than rebuilding the mailbox structure or provider-specific features.
• Cons: Credential handling is the user's responsibility; environment variables are recommended, but no security certifications or compliance claims are made.

Alternatives

For a broader email migration software comparison, consider the category guide.

• Zoho Mail is a better fit for users seeking a hosted mail service with a free plan for up to five users, one domain, and 5 GB of storage per user, rather than a focused command-line migration utility.
• MailJerry may suit users who prefer a migration service with unlimited mailboxes and up to three simultaneous migrations on its free plan; that plan caps each mailbox at 150 MB and use to one device.
• SysTools Email Migration Tool is an option for those who want a free demo covering full mailbox migration for up to two user accounts, with a paid version priced at $35, paid once.
• SysTools Migrator offers a free version for two user accounts and a paid license at from $35 (priced on request), with license quota based on accounts migrated.
• imapsync is another IMAP migration option for readers comparing tools in this category.
• CloudM Migrate is an alternative to consider for migrations involving shared drives or public folders, permissions, folder structure, and version history; its listed plan is priced per 10GB by quote.
• Google Workspace is a paid productivity suite rather than a standalone IMAP folder-transfer tool.
• Cigati Email Migrator offers a free demo limited to the first 100 emails per folder; unlimited migration requires its licensed edition.

Verdict

Choose imap-migrate if you need a free, scriptable way to move a folder between IMAP accounts while retaining dates and flags. Its strongest case is the combination of focused transfer safeguards and no cost; look elsewhere if preserving full mailbox structure or provider-specific features is essential, or if Python setup is a barrier.