To compare Office versions, start with support dates: Office 2016 and 2019 both stopped receiving security updates on October 14, 2025, Office 2021 runs until October 13, 2026, and Office 2024 is supported until October 9, 2029, while Microsoft 365 is a subscription that never goes out of support as long as you pay. Every version shares the same Word, Excel, PowerPoint and Outlook and opens the same files; what changes is the Excel function set, the interface, the bundled apps and how long Microsoft keeps patching it. For a new purchase in 2026, Office 2024 Professional Plus is the best office version for almost everyone.

Office 2016 vs 2019 vs 2021 vs 2024 vs 365: the full comparison

This comparison of Microsoft Office versions covers the Professional Plus edition of each perpetual release, which is what we sell, plus Microsoft 365 Personal for reference. All perpetual keys at OfficeGSM are genuine and licensed for one PC.

What is the difference between Office 2016 and 2024?

Office 2016 was the last version built for Windows 7. Its Excel has the classic function set (VLOOKUP, INDEX and MATCH, SUMIFS) and its interface uses the flat 2013-era ribbon.

Office 2024 is three releases and eight years later. The difference between Office 2016 and 2024 shows up in almost every app: Excel gained dynamic arrays, XLOOKUP, LET, LAMBDA, TEXTSPLIT and GROUPBY; PowerPoint gained Morph, Zoom and Cameo; Word gained a dark document canvas; Outlook got faster search. Office 2024 also drops Publisher and no longer bundles Teams. You can still buy a genuine Office 2016 Professional Plus key for a spare or offline PC, but its security updates ended on October 14, 2025.

What is the difference between Office 2019 and 2024?

Office 2019 was a modest update over 2016. It required Windows 10, added the Excel functions IFS, SWITCH, TEXTJOIN, CONCAT, MAXIFS and MINIFS, brought funnel and map charts, and gave PowerPoint the Morph and Zoom transitions. It was a snapshot of what Office 365 subscribers had received between 2015 and 2018.

The difference between Office 2019 and 2024 is chiefly Excel and longevity. Office 2019 has none of the dynamic array functions, so XLOOKUP, FILTER, SORT, UNIQUE and LET are all missing, along with the 2024 additions. Like 2016, it reached end of support on October 14, 2025. An Office 2019 Professional Plus license still activates and includes Publisher, so it has a place where a matching edition is needed, but for a primary PC we steer customers to 2021 or 2024.

Office 2021 vs 2024: the two versions still in support

These are the only two perpetual releases Microsoft is still patching. Office 2021 introduced dynamic arrays and XLOOKUP to perpetual buyers and adopted the Windows 11 visual style. Office 2024 adds the next wave of Excel functions (TEXTSPLIT, VSTACK, GROUPBY, PIVOTBY, the REGEX family), refines the interface, speeds up Outlook and removes Publisher.

The support gap is the deciding factor: October 13, 2026 for Office 2021 Professional Plus against October 9, 2029 for Office 2024 Professional Plus. We go through the feature changes function by function in Office 2021 vs Office 2024.

Which edition within each version: Home and Student, Home and Business or Professional Plus?

Each perpetual version also comes in editions that differ by app lineup and use rights. Home and Student has Word, Excel, PowerPoint and OneNote for personal use only. Home and Business adds Outlook and permits commercial use. Professional Plus adds Access and (through 2021) Publisher, and is the edition sold through volume licensing. On the Mac side the lineup is Home and Student and Home and Business only; Access and Publisher have never existed on Mac. Our guide to Office Home and Student vs Home and Business covers the edition question in detail. You can browse every version and edition we carry on the Microsoft Office category page.

Support end dates and why they matter more than features

Microsoft gives each perpetual Office release five years of support. When that ends the software keeps working and stays activated, but security vulnerabilities are no longer fixed. Since Word and Outlook open files from strangers all day, an unpatched suite is a real exposure. Microsoft’s Office 2024 lifecycle page and Office 2021 lifecycle page publish the official dates.

1. Office 2016 and 2019: ended October 14, 2025, the same day as Windows 10. Fine for offline or single-purpose machines.
2. Office 2021: ends October 13, 2026. About one year of patches remaining.
3. Office 2024: ends October 9, 2029. Just over three years of patches remaining.
4. Microsoft 365: no end date while the subscription is active.

How to pick and install the right version

1. Check your Windows version. Windows 10 or 11 runs Office 2019, 2021 or 2024; only Office 2016 supports Windows 7 or 8.1.
2. Decide whether you need Publisher (2021 or earlier) or can live without it (2024).
3. Decide whether you need Access. All Professional Plus editions include it; Home and Student and Home and Business do not.
4. Buy the key. The license and the official installer link arrive by email.
5. Uninstall any existing Office version through Settings > Apps, restart, run the installer, then activate in File > Account with Change Product Key. The Office 2024 Professional Plus guide shows each screen, and the process is identical for 2016, 2019 and 2021.

Frequently asked questions

Which is the best Office version to buy in 2026?

Office 2024 Professional Plus. It is the only perpetual release still receiving security updates past 2026 (until October 9, 2029), it has the current Excel function set, and at OfficeGSM it costs about the same as Office 2021. Office 2021 is a reasonable second choice if you need Publisher, since its support runs to October 13, 2026. Office 2019 and Office 2016 both left support on October 14, 2025, so we only recommend them for offline machines or for matching an existing install on other PCs where a like-for-like license is required.

What is the difference between Office 2016 and 2024?

Eight years of development. Office 2024 adds dynamic arrays, XLOOKUP, LET, TEXTSPLIT, GROUPBY and dozens of other Excel functions; a redesigned interface with dark mode; real-time co-authoring on files saved to OneDrive; Morph and Zoom transitions and Cameo in PowerPoint; and a much faster Outlook. It removes Publisher, and it needs Windows 10 or 11 where Office 2016 ran on Windows 7. Most importantly, Office 2016 stopped receiving security updates on October 14, 2025, while Office 2024 is patched until October 9, 2029.

What is the difference between Office 2019 and 2024?

Office 2019 was the last release before dynamic arrays, so its Excel has IFS, SWITCH, TEXTJOIN and funnel charts but not XLOOKUP, FILTER, LET or any spill formulas. Office 2024 has all of those plus the newer TEXTSPLIT, VSTACK and GROUPBY functions. Office 2024 also brings the rounded Windows 11 style interface, full dark mode, better performance and Cameo in PowerPoint. Office 2019 includes Publisher; Office 2024 does not. Support is the decisive gap: Office 2019 ended on October 14, 2025 and Office 2024 continues to October 9, 2029.

Can I still buy and activate Office 2016 or 2019?

Yes. Both still install and activate against Microsoft’s servers, and we sell genuine keys for both. What you no longer get is security patches, because both reached end of support on October 14, 2025. That makes them suitable for a machine that is offline or used only for local documents, or for an organization that needs to add one more seat of an edition already deployed everywhere else. For a computer that receives email attachments and browses the web, we recommend Office 2021 or 2024 instead.

Do all Office versions open the same files?

Yes. Every version since Office 2007 uses the same .docx, .xlsx and .pptx formats, and files travel between 2016, 2019, 2021, 2024 and Microsoft 365 without conversion. The catch is formulas: a spreadsheet built with XLOOKUP or TEXTSPLIT shows #NAME? errors in a version that lacks those functions, and a document using a newer feature may render slightly differently. If you exchange files with colleagues on Microsoft 365, choosing Office 2024 gives you the closest match to what they are using.