Description
This listing activates Office LTSC Professional Plus 2021 on three Windows PCs with a single purchase. It suits small offices, families and freelancers who work across several computers and want the same Office version on each. The key and a direct download link arrive by email, and each PC activates online.
What's included on each of the 3 PCs
Every activated PC receives the complete Office LTSC Professional Plus 2021 suite. There is no reduced set on the second or third machine.
- Word, Excel and PowerPoint LTSC 2021, including XLOOKUP and dynamic arrays in Excel.
- Outlook LTSC 2021 for email, calendar and contacts.
- OneNote for notes and digital notebooks.
- Access LTSC 2021 for desktop databases.
- Publisher LTSC 2021 for print and marketing layouts.
Microsoft Teams is not included in this licence. It is available as a separate free download from Microsoft.
Licence details
| Product | Microsoft Office LTSC Professional Plus 2021 |
|---|---|
| Edition | LTSC (Long-Term Servicing Channel), volume licensing edition |
| Licence type | Perpetual licence, one-time purchase, no subscription |
| Devices | Up to 3 Windows PCs |
| Platform | Windows 10 or Windows 11 |
| Activation | Online on each PC, internet connection required |
| Delivery | Product key and direct download link sent by email |
| Microsoft support status | Security updates end on 13 October 2026. Office keeps working on all three PCs after that date. |
The 3 activations are counted by Microsoft's activation servers. If you replace one of the PCs, contact support@licencehouse.com so we can help with the device change.
System requirements (per PC)
- Windows 10 or Windows 11
- 1.6 GHz or faster processor
- 4 GB RAM, 64-bit system recommended
- 4 GB of free disk space
- Internet connection for download and activation
How to install and activate on three PCs
Direct download: Office LTSC 2021 Professional Plus installer (English, 64-bit). Run the downloaded file to start setup.
You repeat the same short process on each computer. The Office 2021 Professional Plus installation guide shows every screen.
- On the first PC, remove any older Office or Microsoft 365 apps.
- Download the Office LTSC 2021 installer from the link in your order email.
- Run setup, then open Word and go to File, then Account.
- Enter the product key and stay online until activation completes.
- Repeat steps 1 to 4 on the second and third PCs with the same key.
Activate only the three PCs you intend to use. Activating extra PCs uses up the key's activations, which can block a later reinstall.
1 PC or 3 PCs: which Office LTSC 2021 licence?
Choose the 3-device licence when you manage more than one computer. Choose the single licence for one PC only.
| Point | LTSC Pro Plus 2021, 3 PCs | LTSC Pro Plus 2021, 1 PC | LTSC Pro Plus 2024, 3 PCs |
|---|---|---|---|
| Number of PCs | 3 | 1 | 3 |
| Publisher included | Yes | Yes | No |
| Security updates until | 13 October 2026 | 13 October 2026 | 9 October 2029 |
| Supported Windows | Windows 10 and 11 | Windows 10 and 11 | Windows 11 |
For one computer, see Office LTSC Professional Plus 2021 for 1 PC. For support until 2029, the Office LTSC 2024 Pro Plus 3-device licence covers the same number of PCs.
Frequently asked questions
Can I use one Office 2021 key on 3 computers?
Yes, with this listing. One product key activates Office LTSC Professional Plus 2021 on up to three Windows PCs. Install the same edition on each computer and enter the same key. A fourth activation will be refused, so keep track of which PCs you have used.
What happens if I replace one of my three PCs?
Uninstall Office from the old PC first, then install it on the new one. Microsoft may still count the old activation, so the new PC can fail to activate. In that case, email our support team with your order number and we will help with the device change.
Will Office LTSC 2021 still work after October 2026?
Yes. After 13 October 2026, the apps still open, edit and save files on all three PCs. Microsoft only stops publishing security updates. If these PCs handle business email every day, plan a move to Office LTSC 2024, which is supported until October 2029.
Can the three PCs be in different locations?
Yes. The key is not region-locked, so the three PCs can be in different homes, offices or countries. Each PC needs its own internet connection during activation. All three PCs must run Windows 10 or Windows 11, and each one needs the full installation.
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