Microsoft distinguishes between subscription access and a perpetual licence. Its retirement notice says a Microsoft 365 subscriber cannot access Publisher after 1 October 2026. A perpetual installation can continue to run after support ends on 13 October, but it will no longer receive support. Check which edition your organisation actually has before planning a conversion deadline.
The safest archive has two things: untouched Publisher originals and readable copies that you have checked. A PDF is useful for reading and sharing, but does not preserve Publisher editing. If you still have Publisher, make a reference PDF directly from it before the subscription access date. Do a small sample first, including a publication with unusual fonts or linked images.
How do you open and preserve the file?
- Find and back up the source files. Search your computer and shared storage for genuine .pub documents. Keep a copy of each original, along with linked pictures and any fonts you are allowed to retain. Record who owns files that need future editing.
- Export a reference while Publisher still runs. On a licensed Windows installation, open an important publication in Publisher and use File > Save as > PDF, as Microsoft describes. Keep that PDF next to its original.
- Open a representative file on an Apple device. On Mac, iPhone or iPad, first try the included PubHarbor example. Then import a real compatible .pub file. The example does not use one of the three free document openings.
- Inspect the conversion before exporting. Use thumbnails, text search and the compatibility report. Look for substituted fonts, missing linked assets, unsupported objects and changes to page count or line breaks.
- Save and review the reading copy. With PubHarbor Pro, export a searchable multipage PDF or page images. Reopen the file in another reader and compare it with the Publisher reference; keep differences in the archive inventory.
What free options are available?
If you still have access to Publisher on a licensed Windows computer, exporting a PDF there is the most direct route for an existing file. Microsoft documents File > Save as > PDF. A perpetual copy may keep working after support ends, subject to your licence and environment; its continued operation is not the same as support.
Ask the person who sent the .pub file for a PDF if they can still open the original. That often avoids any conversion on your side and gives you a reference for checking another viewer. PubHarbor lets you inspect three distinct imported documents free, with an unlimited included sample; making an export or printing requires Pro.
Online conversion services can be convenient for non-sensitive material, but involve sending the publication to a third party. For private newsletters, customer details or internal documents, check the service terms and your own permission to upload before choosing that route.
What can't it do?
- PubHarbor is a best-effort viewer and archive converter, not a Publisher editor. It never changes the original .pub file.
- Rendering can differ by Publisher generation, missing fonts, linked media and embedded objects. Unsupported objects may appear as diagnostic placeholders.
- An exported PDF is not a certified or pixel-exact facsimile. Compare every important page with a reference before using it.
- The free preview opens three distinct imported documents on this device; the bundled example does not count. Export and print require PubHarbor Pro.
Compare the cover and a dense interior page, not only whether the file opens. Check total pages, headings, line wraps, image crops and any font substitutions. Search the PDF for a phrase you know is present. Record unresolved differences rather than marking a conversion complete.
If the purpose is continued editing, plan a separate authoring workflow. PubHarbor reads and exports compatible publications; it does not create or edit .pub files. Keep the original even if your reading copy looks good, because the PDF is not a replacement for the source.
Frequently asked questions
When does Publisher leave Microsoft 365?
Microsoft says subscribers will not be able to access Publisher after 1 October 2026. Support for the perpetual version ends on 13 October 2026.
Will my existing .pub files vanish?
No. Keep copies of the original files. How you open them later depends on your Publisher licence or a compatible third-party viewer.
Can I open a PUB file on a Mac?
Yes, with a compatible third-party viewer such as PubHarbor. macOS itself has no Publisher decoder, and Microsoft did not release Publisher for Mac.
Is reading free in PubHarbor?
The included example can be reopened without limit and three distinct imported documents can be viewed free on the device. Export and print require Pro.
Can PubHarbor edit a publication?
No. It is a viewer and archive converter. Keep the .pub source for any future editing in another workflow.
Sources and related guides
Microsoft: Publisher retirement and PDF guidance · PubHarbor product facts and compatibility limits