Microsoft has started rolling Grok into Copilot for Word, Excel and PowerPoint. Here is what that actually means, how to turn it on and who cannot use it yet.
1. What is Grok in Microsoft Copilot?
Grok in Microsoft Copilot is a new option that lets Word, Excel and PowerPoint users choose xAI's Grok as the model behind Copilot, alongside the OpenAI and Anthropic models already offered there. Microsoft announced the rollout on its Copilot blog on 12 September 2026, describing it as an expansion of model choice inside Copilot.
This is not a separate Grok app or a new product. It is Grok sitting behind the same Copilot interface people already use inside Word, Excel and PowerPoint, reachable through a model picker rather than through grok.com or the standalone Grok apps.
Microsoft's own account on X confirmed the same rollout, describing it as 'launching even more models in Copilot' and starting with a focused release to customers in the Microsoft Frontier programme, rather than a launch to every Copilot user at once.
2. How do you enable Grok in Copilot?
An administrator has to turn it on first. Coverage of the rollout, including reporting from Windows Central and Office Watch, says access to SpaceXAI's Grok models is controlled by a dedicated admin setting that is switched off by default, so an IT admin has to enable it before anyone in the organisation can pick Grok.
Once that setting is on, a user opens Copilot inside Word, Excel or PowerPoint and finds Grok listed in the model picker alongside GPT and Claude. From there you can either let Copilot automatically choose the best model for a task, or manually select Grok yourself for that document or session.
Picking a model in Copilot now means picking whose AI reads your document, not just how it answers.
3. Grok Copilot Word Excel PowerPoint: who can actually use it?
Access is narrower than a normal feature rollout. It requires an eligible Microsoft 365 Copilot licence, enrolment in Microsoft's Frontier programme, which is Microsoft's early-access track for testing new Copilot capabilities before wider release, and the admin setting described above switched on for your organisation.
Microsoft has framed this as a focused preview rather than general availability, intended to gather feedback on how people actually use Grok for everyday document, spreadsheet and slide work before deciding whether to expand it further.
4. Which Grok model powers Copilot?
Microsoft has not said. Its announcement and the reporting around it do not name a specific Grok version, so treat any claim that a particular model, such as Grok 4.6, sits behind this integration as unconfirmed until Microsoft or xAI states it directly.
That is worth knowing before you compare quality against grok.com or the Grok apps, since Copilot's Grok could behave differently depending on which underlying model and system prompt Microsoft has configured for it.
5. Grok vs GPT vs Claude in Copilot: how do you choose?
Copilot's model picker now covers three families with very different training and behaviour, and none is a fixed winner for every task. Windows Central reported that Microsoft has tuned Grok's system prompt inside Copilot to stay strictly professional, so do not expect the looser tone Grok can have on grok.com or X to carry over into Word or Excel.
The practical approach is the same one worth taking with any multi-model tool: try the same real task, such as drafting a memo, cleaning up a spreadsheet formula or outlining a slide deck, on more than one model and judge by the output rather than by which brand is newer. Auto-select is a reasonable default until you have a specific reason to pin one model.
6. Why is Grok not available in Europe or the UK?
Microsoft's own rollout details, echoed across multiple outlets covering the announcement, state that Grok is not being offered to Frontier customers in the European Union, the European Free Trade Association or the United Kingdom during this preview. Microsoft has not published a public reason for the exclusion alongside the announcement.
If you are in one of those regions and do not see Grok in your model picker even with Frontier access and admin approval, that is expected for now rather than a fault on your end. Check Microsoft's own Copilot and Frontier pages for the current status before assuming it will never arrive there.
7. Is your data safe when you use Grok in Copilot?
Choosing Grok inside Copilot sends that request to xAI's infrastructure rather than keeping it entirely within Microsoft's own models. Coverage of the rollout notes that Microsoft has added SpaceXAI, xAI's parent company since its 2026 merger, to its Online Services Subprocessor List, which is Microsoft's public disclosure of outside companies that may process customer data on its behalf.
For organisations with strict data residency or vendor rules, that subprocessor relationship is worth reviewing with your own compliance team before switching Grok on, in the same way you would review any third-party model added to an existing Microsoft 365 environment.
8. The bottom line
Grok reaching Copilot is a genuine expansion of Microsoft's multi-model strategy, and it gives Word, Excel and PowerPoint users a real reason to compare Grok against GPT and Claude on their own documents rather than in a separate chat tab. It is not, however, a feature every Copilot user can switch on today.
Takeaway: if you have Frontier access and admin rights, it is worth a short trial on a real document to see how Grok's tuned, professional tone compares with your usual model. If you are outside the Frontier programme, in the EU, EFTA or UK, or waiting on an admin, the sensible move is to keep using grok.com or the Grok apps directly and revisit Copilot access once Microsoft widens the rollout.