Microsoft is shutting down Publisher. The desktop publishing app, part of Microsoft 365, will stop working for subscribers on October 1, 2026. Users who bought a perpetual license will lose support on October 13, 2026. The company is telling anyone with files in the proprietary .pub format to convert them before then.
Two deadlines, two groups of users
The October 1 cutoff hits Microsoft 365 subscribers first. That's the version most people get through a monthly or yearly plan. After that date, the application won't launch, and .pub files won't be openable in Publisher. The October 13 date applies to perpetual-license editions, the ones you buy once and own outright. On that day, Microsoft stops supporting them entirely — no updates, no security patches, no help.
That's a thin margin. A subscriber and a perpetual-license user get about a year and a half from today, but the difference between them is just twelve days.
Why .pub files are the real problem
Publisher saves everything as .pub. That format is proprietary, meaning no other mainstream program opens it natively. When Publisher goes away, those files become orphans unless you've moved them first. Microsoft's guidance is straightforward: export .pub files to PDF, or migrate them to other tools. There's no mention of a built-in converter to another format.
A PDF is a good escape hatch. It's viewable everywhere, it keeps the layout intact, and it doesn't need a dedicated app. But a PDF is a final snapshot. If you need to keep editing a document later, PDF won't cut it. You'd have to move to a different publishing program and either import or rebuild the file there.
What to do with your .pub files now
Start by inventorying. Look through your drives for anything ending in .pub — old newsletters, brochures, flyers, labels, invitations. For each file, decide whether it needs to stay editable. If yes, find a replacement tool that can handle the import, or be prepared to rebuild it from scratch. If no, export it to PDF and move on.
There's no auto-conversion coming. Microsoft hasn't indicated any grace period, no extension, no special tool. The shutdown date is the shutdown date. Subscribers have until October 1, 2026. Perpetual users have until October 13, 2026. Any .pub file left unconverted after that is at risk.
