Microsoft is putting SpaceXAI’s Grok models into Microsoft 365 Copilot inside Word, Excel, and PowerPoint — web and desktop — for Frontier-eligible tenants whose admins opt in. For organisations already paying for Copilot, that means model choice lands in the Office apps people already live in, instead of bouncing out to a separate chat tool.
Microsoft announced the expansion on 12 September 2026 in Expanding model choice in Copilot with Grok.
Grok has now become an optional model choice inside drafts, sheets, and decks, rather than a marketplace add-in that needs to be separately sought out and bolted in. The AI-provider switch however, does start off, so Enterprise admin teams will need to turn on SpaceXAI as a provider before anyone sees Grok in those apps.
What IT Has to Flip On
Access rolls out through the Microsoft Frontier Program. Microsoft Learn’s Connect to SpaceXAI models page puts the control in the Microsoft 365 admin centre under Copilot → Settings → AI providers for other large language models → SpaceXAI, and a Copilot licence is required. SpaceXAI is also on Microsoft’s Online Services Subprocessor List.
Notably, opt-in is not just a cosmetic switch. Data sent to Grok is processed outside Microsoft-managed environments under xAI’s enterprise terms and DPA, per Learn. That means the model choice comes with a different processing path than Microsoft-hosted models alone.
Security and compliance teams will need to review that path before any end users get to picking Grok in the ribbon. Microsoft says models still go through testing, safety validation, and Responsible AI reviews before customers see them, as they normally do.
Who Gets It — and Who Does Not
Eligible Frontier organisations that flip the setting on can choose Grok when they draft in Word, analyse in Excel, or build decks in PowerPoint. Leave the setting off and Copilot keeps its prior model path.
Frontier customers in the EU, EFTA, and UK are held out of this preview with no published return date, so the Office Grok path is not global yet.
With Grok spreading its wings as a model outside the direct SpaceXAI ecosystem, adoption will likely continue growing, especially as it becomes more capable. Broader Copilot surfaces such as Teams and Outlook, general Copilot tiers outside Frontier, and access to Grok Bot through Microsoft Enterprise might be future items to look forward to.
Microsoft says it will weigh feedback, usage, and product fit before widening beyond this Frontier preview. The useful question for most tenants right now is whether IT will opt in for Word, Excel, and PowerPoint, not whether every Copilot surface already has Grok.
