Short answer: Choose Office 2024 if you want a one-time purchase that works offline with no subscription. Choose Microsoft 365 if you want continuous updates, cloud storage, and Microsoft's subscription services on several devices. Avoid buying Office 2021 for a main PC: its support ends on October 13, 2026.
Last updated: October 4, 2026. By the USTrustedTech Editorial Team.
Support end dates
| Product | Type | Support ends |
|---|---|---|
| Microsoft 365 | Subscription | Continues while you stay subscribed and keep updating |
| Office 2024 | One-time purchase | October 9, 2029, with no extended support afterward |
| Office 2021 | One-time purchase | October 13, 2026, with no extended support afterward |
Check Microsoft's lifecycle pages for the latest dates before you buy. Already on Office 2021? Read what to do before the deadline.
Full comparison
| Feature | Microsoft 365 | Office 2024 | Office 2021 |
|---|---|---|---|
| Payment | Recurring subscription | One-time | One-time |
| Word, Excel, PowerPoint, Outlook | Yes (plan dependent) | Yes (edition dependent) | Yes (edition dependent) |
| New features after release | Yes, continuous | No, security fixes only | No |
| Cloud storage and Microsoft services | Included, varies by plan | Not included | Not included |
| Copilot AI features | Depends on your plan and Copilot licensing | Not part of a perpetual license | Not part of a perpetual license |
| Devices | Multiple, varies by plan | One PC or Mac per license | One device per license |
| Works offline | Yes, with periodic check-ins | Yes | Yes |
| Stops working if unpaid | Yes | No | No |
Plan details change, so check Microsoft's current plan page for exact apps, storage and Copilot availability.
Which should you buy?
Choose Office 2024 if:
- You want to pay once and avoid renewal fees
- You need the core desktop apps for everyday documents, spreadsheets and email
- You are installing on a single Windows PC or Mac
- You prefer a stable, fixed version
Choose Microsoft 365 if:
- You want cloud storage, collaboration tools and always-current apps
- You work across several devices
- You want access to Microsoft's AI features where your plan includes them
- You want to share a plan with family members (Family plan)
Choose Office 2021 only if:
- You need the lowest price for an older or secondary machine and accept that support ends October 13, 2026
Is a one-time purchase cheaper?
It depends on how long you will use it. Take your actual Microsoft 365 renewal quote, multiply it by the number of years you plan to use Office, and compare the result with the one-time price of the edition you need. Our guide to the Microsoft 365 price increase shows how to run that comparison.
Office 2024 editions explained
| Edition | Best for | Commercial use |
|---|---|---|
| Home | Personal and student use, core apps | No, personal use only |
| Home & Business | Small business, includes Outlook | Yes |
| Professional / Professional Plus | Power users and businesses needing extra apps | Yes |
App lists differ by edition and by PC or Mac, so check the product page before you buy.
Common mistakes to avoid
- Buying a Home edition for business use. Home licenses are for personal use. Choose Home & Business or a Professional edition for work.
- Expecting cloud services with Office 2024. A one-time license does not include a Microsoft 365 subscription.
- Installing one license on two PCs. Each license covers one device.
- Buying Office 2021 for a PC you plan to use for years. Support ends in October 2026.
Shop Office licenses
- Browse all Microsoft Office licenses
- Office Home 2024 (1 PC)
- Office 2024 Pro Plus
- Office 2021 Home & Student
- Office 2024 + Windows 11 Pro bundle
After buying, follow our guides to install Office 2024 and activate Office 2024. Buying from a third-party seller? Read Is it legal to buy a third-party Windows or Office license? first.
Why customers buy from ustrustedtech
- Money-back guarantee on bad keys. If a key is invalid, already used, or fails to activate, email us for a full refund or a replacement key. Refunds are not available after a key has been successfully activated.
- Fast digital delivery. Your key and activation instructions are emailed to you, typically within minutes and within 12 hours at most.
- 24/7 support at support@ustrustedtech.com.
- A real US business address: trustedtech, 5171 California Avenue, Irvine, CA 92617, United States.
Frequently asked questions
What is the difference between Office 2024 and Microsoft 365?
Office 2024 is a one-time purchase with a fixed feature set. Microsoft 365 is a subscription that adds continuous updates, cloud storage and Microsoft services, with details depending on your plan.
When does Office 2024 support end?
Office 2024 is supported until October 9, 2029, with no extended support afterward.
When does Office 2021 support end?
Office 2021 support ends on October 13, 2026, with no extended support afterward.
Does Office 2024 work on Mac?
Yes. Office 2024 is available for Windows and Mac. Pick the version that matches your operating system.
Does Office 2024 include Teams or Copilot?
No. Those services are tied to Microsoft 365 subscriptions and Microsoft's Copilot licensing, not to a one-time Office license.
Can I use Office 2024 offline?
Yes. It is installed locally and works offline. An internet connection is needed for activation and optional online features.
Can I install Office 2024 on more than one PC?
Each license covers one device. A second PC needs a second license.
