imap-migrate vs SysTools Migrator

imap-migrate is a free, open-source command-line tool for transferring the contents of one email folder between IMAP hosts. It can work with providers that support IMAP, including Gmail, Outlook, Fastmail, Yahoo and custom servers. The tool preserves original received dates and flags such as Seen and Flagged, and shows progress, transfer speed, success and error counts, plus estimated time remaining. It records actions in migration.log. Its README says interrupted migrations can be rerun without duplicating emails; the --dry-run option checks connection and settings without moving messages. Credentials can be supplied as command-line arguments or environment variables, with environment variables recommended by the README as the more secure option. Both accounts need IMAP access enabled, and the tool requires Python 3.12 or higher; uv is recommended for dependency management. It runs on Linux, macOS and Windows and is licensed under MIT. It does not rebuild a full folder structure or migrate provider-specific features such as Gmail labels or categories. Bug reports and contributions are invited through GitHub issues and pull requests.

SysTools Migrator transfers mailbox and related data between cloud platforms. It handles email, contacts, calendars, documents, attachments, files, groups, and other listed mailbox data, with routes involving Microsoft 365, Google Workspace, Google Drive, OneDrive, SharePoint, Microsoft Teams, Exchange, Lotus Notes, IMAP, Domino, Zimbra, and Google Vault. Users can choose data categories and date ranges, prioritize users, and monitor progress in real time. Batch and concurrent multi-user migration, reports, and delta migration for data that arrives after an initial transfer are supported. The product runs on Linux and Windows and supports tenant-to-tenant moves. Its product page lists OAuth 2.0 authorization for Office 365, encryption, and ISO 9001:2015 and ISO 27001:2013 certifications. The free version costs nothing and migrates email for 2 user accounts. The paid version costs what you agree with the maker; its license quota is based on user accounts migrated. Free 24x7 support is advertised.