ChatGPT vs Copilot vs Claude for business

ChatGPT, Microsoft Copilot and Claude are the three AI assistants most businesses weigh up. All three are good at the everyday work: drafting emails and proposals, summarizing long documents, answering questions and working through a spreadsheet. The real differences for a business are what you already pay for, where your email and files live, and what happens to the information your staff type in.

Prices and terms checked against each company’s own pages on September 25, 2026. US prices per person per month, before tax.

The short answer

• You use Microsoft 365 (Outlook, Teams, SharePoint): start with Copilot. The basic version is already included, and the paid seat works inside the apps your team lives in.
• You don’t use Microsoft 365: a business plan of ChatGPT or Claude is usually the better fit. Copilot’s advantages depend on your email and files being in Microsoft 365, and switching just for Copilot rarely pays.
• Whichever you pick: put staff on a business plan with their work account, not personal accounts. That’s the difference that matters most for your data.

What each costs

The paid seats cost about the same. The real saving is the free tier: if you already pay for Microsoft 365, every employee can use Copilot Chat today at no extra cost, and you only buy paid seats for the people who’ll use them heavily. Our guide to the five levels of Copilot explains what each step adds.

What happens to your data

This is where the plan matters more than the brand.

• Business plans (Copilot with a work account, ChatGPT Business, Claude Team and Enterprise) don’t use your business data to train their AI models by default.
• Free and personal plans (ChatGPT Free, Plus and Pro; Claude Free, Pro and Max) may use conversations to improve their models unless the person opts out, and they aren’t covered by a business contract.
• Copilot with a work account is covered by the same Microsoft agreement as your company email and files. Look for the shield icon at the top of Copilot Chat: it means that protection is on.

Health practices: Microsoft Copilot and Copilot Chat are in scope of Microsoft’s HIPAA business associate agreement when properly set up; web searches are not. For any AI tool, get the signed agreement and check exactly what it covers before patient information goes in.

Working with your email and files

The biggest practical difference is where each assistant lives. Copilot is built into Outlook, Teams, Word, Excel and PowerPoint, only shows people what they already have permission to open, and is managed from the same Microsoft 365 admin center as everything else. It also uses models from OpenAI and Anthropic, the companies behind ChatGPT and Claude, under Microsoft’s data protection terms.

ChatGPT and Claude can now connect to SharePoint, OneDrive, Outlook and Teams too, once an admin approves it, so the gap is narrower than it was. The difference is that they work alongside those apps as a separate tool, rather than inside them. For a business that doesn’t use Microsoft 365 at all, that’s no disadvantage.

Which one for which business

Using more than one

Plenty of businesses end up with two: Copilot for the work that touches their Microsoft 365 email and files, and a ChatGPT or Claude seat for someone who writes, researches or analyzes all day and prefers it. That’s fine, as long as both are business plans and everyone knows which one gets customer information.

Whichever you choose, the assistant is only the start. The hours come from connecting it to the work: agents that answer from your own documents, and automations that send the quote or chase the invoice. SeeHow to find the tasks AI can take off your plate to work out where to begin.