imap-migrate vs Priasoft Migration Suite for Exchange

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.

Priasoft Migration Suite for Exchange moves Exchange mailboxes between Exchange environments and to Office 365, also called Exchange Online. Listed source versions include Exchange 5.5, 2000, 2003, 2007, 2010, 2013, 2016, and 2019, with some same-forest scenarios dependent on Microsoft mixed-mode support. The suite supports repeatable dry runs that use the same operations while isolating target objects before production. Migration runs on the wire without first copying data through a temporary file. It can capture mailbox folder delegate details and restore resolved permissions in the target environment. Outlook profile update technology supports standard and RPC over HTTP profiles and cached-mode adjustments, while MAPI/HTTP is listed for Office 365 connections. Calendar and contact migration, tenant-to-tenant moves, staged migration, and Microsoft 365 support are listed capabilities. The product runs on Windows and can be self-hosted. A valid license is required to migrate objects, with licensing metered by processed objects; an evaluation license is available by request. Pricing is on request, and a free trial is advertised.