A Slack import keeps guests as guests and private history private

2 October 2026

Single- and multi-channel guests in a Slack export are invited as guests, into the channels Slack listed them in and never #general. A private Slack channel’s history goes into a private channel of its own (a new one, such as #operations-2, when the name is taken by a public channel). Channels are matched by name when the import runs again, so nothing is made twice, and messages by people who have joined since become theirs.

Every imported message is marked as brought in from Slack, with who imported it and when, and every page of an import is in the audit log. Dates outside 2013 to today are left out. The export is read in your browser within size limits, the file chooser is a proper button, and an import where a channel fails names why, with Try again.