Open-source alternatives to Microsoft Office

Microsoft 365 is one of those bills everyone pays and nobody questions. It's a monthly fee per person, for as long as you're in business, and for a lot of small firms the honest usage is a few letters, a price list in Excel and a presentation twice a year.

So here's the question worth asking: does everyone in the building really need it? The warehouse PC that opens one spreadsheet? The part-timer who types the odd letter?

LibreOffice is the long-standing free alternative. It's a proper desktop office suite, and it doesn't need a server, an account or a subscription. That makes this page a bit different from the others on the site, because there's nothing to host.

LibreOffice

LibreOffice comes from The Document Foundation, and the current release, 26.8, came out on 26 August 2026. You download it, install it and start typing. There's no sign-up.

You get six apps in one install:

• Writer, the word processor, for anything from a quick note to a full-length book.
• Calc, the spreadsheet, with charts and data analysis.
• Impress for presentations.
• Draw for diagrams and illustrations.
• Base for simple databases with forms and reports.
• Math for formulas.

It opens and saves Microsoft's formats, including .docx, .xlsx and .pptx, and you can set those as your default save format so colleagues and customers never notice. If you've got a folder full of old Office files, there's also a wizard for converting them in one go.

It's also light. The minimum is 256 MB of memory on Windows and Linux, or 512 MB on a Mac, and around 1.5 GB of disk at most. It runs on Windows 10 and 11, macOS 11 or later, and modern Linux, so it'll give an older PC a useful second life.

The latest release makes a point of having no generative AI features, and the Foundation says nothing needs network access to work. Whether that's a plus or a minus depends on you, but if you want your documents kept on your own machine, it's a clean answer. If you've got used to Copilot, you'll miss it.

Now the catch, and this is the thing to test before you commit: macros. Microsoft Office uses VBA, and LibreOffice uses its own Basic. They're similar, but LibreOffice's own help says macros generally can't be shared without editing. Some Excel macros will run if you switch on an option, but don't rely on that. If the business runs on a clever spreadsheet someone built in 2011, open it in LibreOffice before you cancel anything.

Complicated layouts need the same care. A simple letter will be fine. A heavily formatted Word template or a bid document with tracked changes bouncing between companies is where you want to test first.

Which one?

My pick is a mixed setup: LibreOffice as the default, keeping Microsoft 365 for the few people who need it. Most small firms have a handful of heavy users and a lot of light ones, and you don't have to move everybody or nobody.

• Main drawback: Excel macros and complex Word templates may not carry across cleanly.
• All-in on LibreOffice if your documents are simple and your email is already somewhere else.
• Stay on Microsoft 365 if you live in Teams, Outlook and shared documents, or swap complicated files with customers every day.

One thing that's easy to forget: Microsoft 365 business plans aren't really an office suite. They also cover your email, file storage and meetings, depending on the plan. Cancel the subscription and those go too, so have a plan for them first. There's a separate page on this site for file storage.

The UK angle

There's no real privacy argument for most small firms here. Microsoft 365 is a perfectly sensible choice for a UK business. If your organisation's default location is the UK, Microsoft says your core data such as mailboxes and OneDrive files stays in UK datacentres, and it lists Cardiff, Durham and London. You can check yours on the Data Location card in the admin centre.

LibreOffice's angle is simpler. Documents stay on your own computers and wherever you choose to save them. Nothing goes to a cloud service unless you put it there. That's handy if you handle sensitive documents, but it also means backups are your problem, so sort those out before anything else.

The file format matters too. LibreOffice's native format, OpenDocument, is an open standard, so you aren't tied to one company to read your own records in 20 years' time.

Honest drawbacks

• Macros don't reliably move across. Budget time to test or rewrite them.
• Complex formatting can shift, especially in files that go back and forth with Word users.
• It's desktop software. You don't get the shared, live editing in a browser that Microsoft 365 includes.
• Copilot, Teams and Outlook aren't replaced. LibreOffice covers documents only.
• No vendor support. The Document Foundation doesn't provide technical support itself. Help comes from forums, mailing lists or paid partners, and it recommends those partners' Enterprise versions for large organisations rather than the free download.
• People need a little retraining. The menus are familiar, but they aren't the same as Office's ribbon, and staff will grumble for a fortnight.

Need a spreadsheet replaced?

If the real reason you can't leave Excel is a business-critical spreadsheet full of macros, it may be better as a small web app, and the team at Dev Partners can build that for you.

Sources

• LibreOffice licences
• LibreOffice: what's included
• LibreOffice system requirements
• LibreOffice in business
• LibreOffice help: information for Microsoft Office users
• IT Brief UK: LibreOffice 26.8
• Microsoft 365 plans and pricing (US)
• Microsoft 365 datacenter locations
• Microsoft 365 data location FAQ
• Microsoft 365 product terms data residency