Office 2016, Office 2019, Office 2021 and Office 2024 all carry the same internal version number, 16.0, so the year in the name is the quickest way to tell them apart. What really separates them is how long Microsoft supports each one, which systems it runs on and which apps come in the box. This guide puts all four side by side and explains which one makes sense to install from October 2026 onwards.
| Point of comparison | Office 2016 | Office 2019 | Office 2021 | Office 2024 |
|---|---|---|---|---|
| First released | 2015 | 2018 | 2021 | 2024 |
| Support ended or ends | 14 October 2025 | 14 October 2025 | 13 October 2026 | October 2029 |
| Security updates today | No | No | No | Yes |
| Install technology | Click-to-Run or Windows Installer (MSI) | Click-to-Run | Click-to-Run | Click-to-Run |
| Windows listed by Microsoft | Windows 11, Windows 10, Windows Server 2016 | Windows 11 and Windows 10 | Windows 11 (LTSC 2021: Windows 11 and Windows 10) | Windows 11 (plus some LTSC and Server releases for the LTSC edition) |
| Publisher | Publisher 2016 available | Included in Professional Plus | Included in Professional Plus | Not included in any edition |
| Mac version | Office 2016 for Mac (support ended 2020) | Office 2019 for Mac (support ended 2023) | Home & Business 2021 for Mac | Home & Business 2024 for Mac |
What are the main differences between Office 2016, 2019, 2021 and 2024?
The main differences are support status, operating system support and the app line-up: Office 2016 and 2019 lost support on 14 October 2025, Office 2021 followed on 13 October 2026, and only Office 2024 still receives security updates, while newer versions add Excel functions, drop Publisher and install only with Click-to-Run.
All four are one-time purchase (perpetual) versions, so none of them needs a subscription. Microsoft's guide to installing different Office versions on the same computer confirms that every release from Office 2016 to Office LTSC 2024 uses version 16.0.
The advanced nuance is that the shared version number causes install conflicts. Because two Click-to-Run versions with overlapping apps cannot sit on one PC, you normally remove the old version before installing the new one, as our guide to completely uninstalling old Office explains.
When does support end for each Office version?
Microsoft ended support for Office 2016 and Office 2019 on 14 October 2025 and for Office 2021 and Office LTSC 2021 on 13 October 2026, while Office 2024 and Office LTSC 2024 are supported until October 2029, so Office 2024 is the only one of the four that still receives security fixes.
The dates come from Microsoft's lifecycle pages, such as the Office 2019 lifecycle entry. Office 2016 and 2019 followed the Fixed Lifecycle Policy with mainstream and extended phases. Office LTSC 2021 and LTSC 2024 get five years of mainstream support and no extended support, while the consumer editions of 2021 and 2024 follow the Modern Lifecycle Policy.
The cause and effect matters more than the date. When support ends, Microsoft stops releasing security fixes for newly discovered vulnerabilities, so every new flaw found in Word, Excel or Outlook stays open on that PC. Microsoft also states that connecting Office 2016 and 2019 to Microsoft 365 services has not been supported since October 2023.
For a deeper look at what this means for older installs, read our guide to Office 2019 end of support and your upgrade options.
Which Windows and macOS versions does each Office version support?
Microsoft lists Windows 11, Windows 10 and Windows Server 2016 for Office 2016, Windows 11 and Windows 10 for Office 2019 and Office LTSC 2021, and Windows 11 for Office 2024, while Office 2021 and 2024 for Mac are supported on the three most recent versions of macOS.
Office LTSC 2024 has a slightly wider list than the consumer edition. Microsoft names Windows 11, Windows 11 LTSC 2024, Windows 10 LTSC 2021 and 2019, and Windows Server 2022 and 2025. For Arm-based PCs, Windows 11 is the minimum for Office 2024.
On a Mac the picture is simpler. Office 2016 for Mac and Office 2019 for Mac are both out of support, so a Mac buyer today is choosing between the 2021 and 2024 Home & Business editions, and our Office 2024 for Mac install guide covers the newer one.
Remember that Windows 10 itself reached end of support in October 2025. Running supported Office on an unsupported Windows still leaves the operating system unpatched, which our guide to Windows 10 end of support explains.
What did each Office version add?
Each version built on the last: Office 2016 brought Tell Me, co-authoring and new chart types, Office 2019 added Excel functions such as IFS and TEXTJOIN plus PowerPoint Morph and Zoom, Office 2021 introduced XLOOKUP and dynamic arrays, and Office 2024 added the IMAGE function, dynamic charts and a refreshed design.
- Office 2016: Tell Me search, co-authoring in Word and PowerPoint, one-click forecasting in Excel, and Treemap, Waterfall, Pareto, Histogram, Box and Whisker and Sunburst charts.
- Office 2019: CONCAT, IFS and TEXTJOIN in Excel, Morph and Zoom in PowerPoint, LaTeX equations in Word, 3D models and icons.
- Office 2021: XLOOKUP, XMATCH and LET, dynamic array functions such as FILTER, SORT and UNIQUE, and OpenDocument Format 1.3 support.
- Office 2024: the IMAGE function, charts that follow dynamic arrays, 14 new text and array functions, Word session recovery and OpenDocument Format 1.4.
All four versions use the same .docx, .xlsx and .pptx file formats, so documents open in each of them. The catch is formulas: a workbook built with XLOOKUP or FILTER will not calculate properly in Office 2016 or 2019, because those functions do not exist there. Our Office 2024 vs Office 2021 comparison covers the newest changes in detail.
Which Office versions include Publisher?
Publisher was part of the Professional Plus suites of Office 2019 and Office LTSC 2021, and Publisher 2016 also exists, but Office 2024 and Office LTSC 2024 do not include Publisher in any edition, because Microsoft retired the app, with support for perpetual versions ending in October 2026.
According to Microsoft's Publisher retirement notice, people who own a perpetual version can still install and use it and still open their files, but without support. Microsoft 365 subscribers lost access to the app.
What we commonly see in support is a buyer who chooses Office 2024 and later finds that old .pub files will not open. If you rely on Publisher, keep a copy of an older version on one PC or convert your files to PDF or Word before you move.
Why do some people still buy Office 2016 or Office 2019?
People still buy Office 2016 or 2019 mainly for compatibility: an older add-in, macro or line-of-business tool that was only tested with that version, a fleet of PCs that must match, or a Windows Installer (MSI) deployment, which only Office 2016 offers, while accepting that neither version receives security fixes any more.
Office 2016 is the only one of the four that can be installed with MSI, which some older management tools expect. It also lists the most modest hardware requirements of the group, with 2 GB of RAM on Windows.
The trade-off is security. A PC running unsupported Office should not be your main machine for opening email attachments or files from unknown senders. If compatibility is the reason, our Office 2016 Professional Plus licence covers that need, but plan your move to a supported version.
Which Office version should you install today?
For most people, Office 2024 is the version to install today, because it is the only perpetual release still supported, until October 2029, while businesses that manage several PCs can choose Office LTSC 2024 and anyone who wants continuous new features can choose a Microsoft 365 subscription instead.
| Your situation | Suggested version |
|---|---|
| Home user or freelancer on one PC or Mac | Office Home & Business 2024 |
| Windows user who needs Access | Office 2024 Professional Plus or LTSC Professional Plus 2024 |
| Small office with several PCs | Office LTSC 2024 (Standard or Professional Plus) |
| Legacy add-in or older system | Office 2016 or 2019, ideally on an isolated PC |
| Wants new features every month | Microsoft 365 |
If you are torn between the two main 2024 editions, our guide to Office 2024 Home & Business vs Professional Plus lays out the differences. You can compare every edition we stock in our Microsoft Office for PC and Mac collection.
Frequently asked questions
Is Office 2016 still supported?
No. Microsoft ended support for Office 2016 on 14 October 2025, the same day as Office 2019. The apps may continue to work, but Microsoft no longer releases security fixes, bug fixes or technical support for them, so newly found vulnerabilities stay unpatched on any PC that still runs Office 2016.
Can I still use Office 2019 after end of support?
Yes, Office 2019 keeps opening and saving files after end of support, and your licence remains valid. However, it no longer receives security updates, and Microsoft does not support connecting it to Microsoft 365 services, so features such as Exchange Online mail or OneDrive integration may become unreliable over time.
Which Office version works best with Windows 11?
Office 2024 is the best match for Windows 11, because it is supported until October 2029 and Microsoft lists Windows 11 as its required operating system. Older versions such as Office 2019 and 2016 can install on Windows 11, but they no longer receive security updates.
Can Office 2016 open files made in Office 2024?
Yes, in most cases. Office 2016 and Office 2024 use the same .docx, .xlsx and .pptx formats, so documents open normally. Problems appear with newer features, for example Excel formulas that use XLOOKUP, FILTER or IMAGE, which older versions cannot calculate because the functions do not exist there.
Is there a newer version than Office 2024?
Office 2024 is the newest one-time purchase version of Office for home and business users at the time of writing. Microsoft 365 is the subscription alternative that receives new features continuously. Our guide on whether there is an Office 2025 explains how Microsoft names and releases new perpetual versions.