The short version
- Copilot fits teams living in Microsoft 365. Grok fits teams living on X.
- ChatGPT and Claude are strong all-rounders with business plans that don't train on your data by default.
- Pick one, connect it to your data and train people. Consistency beats the 'best' model.
Ask five business owners which AI assistant is best and you'll get five answers. They're probably all right, for their business.
The four big names have settled into distinct roles.
| Assistant | Home turf | Best for |
|---|---|---|
| Microsoft Copilot | Word, Excel, Outlook, Teams[1] | Email, meetings and documents in Microsoft 365 |
| ChatGPT | Its own app, plus Drive, SharePoint and Dropbox connectors[2] | All-round drafting, analysis and custom team assistants |
| Claude | Its own app, connected to your tools | Careful writing, long documents and reasoning[3] |
| Grok | X and Grok.com[4] | Real-time trends, plus always-on Grok Bot agents[5] |
The privacy question
Both OpenAI and Anthropic say their business plans don't train on your content by default.[2][3] Whatever you choose, the rule is the same: business data goes in a business account, never a personal one.
How to choose
Start with where your team spends its day. If it's Outlook and Teams, Copilot has the home-ground advantage. If you need a strong general assistant, trial ChatGPT and Claude side by side on your three most common tasks. If you live on X, Grok earns a look.
Then commit. A team that shares one assistant, one set of saved workflows and one way of working will beat a team where everyone uses something different.
Sources
- Microsoft Australia: Microsoft Copilot for small business
- OpenAI: ChatGPT for business
- Claude: plans and pricing
- xAI: Grok
- xAI docs: Grok Bot overview (updated 28 Oct 2026)
Sources checked 7 November 2026. Product features and prices change often, so check the vendor's site before you buy.