ChatGPT or Copilot for your business?

ChatGPT or Copilot is, for most small businesses, not a question of which model is smarter but of where your work already lives. Choose Copilot if your business runs on Microsoft 365: it reads along in Outlook, Teams, Word and Excel, with the permissions already set, for 18.20 euros per user per month on a yearly contract (21 dollars in the US, with a first-year promotion in euros until the end of 2026). Choose ChatGPT if you work in Google Workspace or a mix of tools, or want a broad workspace for writing, analysis and images: ChatGPT Business costs 21 euros per user per month, or 20 dollars billed yearly. If the assistant has to answer from all your own documents, with permissions per person, a solution of your own fits better than either.

If you want to go further than an assistant, see what AI for business can do on your own data.

The same kind of help, in a different place

Both run on language models that write, summarise, translate and explain. The difference is context: what the assistant knows about your business at the moment you ask.

Microsoft 365 Copilot sits in the programs your team has open all day. In Outlook you ask it to summarise a long thread, in Teams for the action points of the meeting that just ended, in Word for a first draft based on an existing quote, in Excel to explain why one month is off. Copilot works with what you may see in Microsoft 365: your mail, calendar, chats and files.

ChatGPT stands apart from your other software. In the business plan you set up projects with their own files and instructions, share custom assistants with colleagues and switch on connectors to tools you already use. ChatGPT knows about your business what you give it: a file you upload, text you paste, a connector you open.

You feel that difference every day. With Copilot you move nothing, but you are tied to the Microsoft world. With ChatGPT you choose what you share, but you have to do it yourself.

What ChatGPT and Copilot cost

Microsoft prices exclude VAT, and euro prices differ slightly per country. What ChatGPT costs per plan, personal plans included: ChatGPT pricing. Weighing other assistants too? Read ChatGPT vs Claude and ChatGPT vs Gemini.

Worked example: ten staff, one year

An accounting firm with ten people on Microsoft 365 Business Standard. Four spend the day in mail and meetings, six work mostly in their accounting package. With Copilot the four each save 3 hours a week and the six 1 hour, over 46 weeks. We count 45 euros of wage cost per hour and euro prices without the promotion. With ChatGPT the four save an hour less, because they move their mail over themselves. Mixed means: Copilot Chat for everyone and a paid Copilot licence for the four; the six then save half an hour a week. The time saved is an example; measure your own.

In this example Copilot for everyone wins, because the firm works in Microsoft 365. But the gap with the mixed approach hangs entirely on that one hour a week for the other six. If your team does not reach it, mixed is the better choice: you pay only for those who really work in it every day. Measure it first with a six-week pilot, as described in AI implementation in your business.

What happens to your business data

Which agreements to make: the EU AI Act for business; whether you need a written policy: do I need an AI policy.

Copilot wins if your business runs on Microsoft 365

An accounting firm that has worked in Outlook, Teams and SharePoint for years has the shortest route with Copilot. Nobody has to learn a new program, you manage licences in the same place as your mailboxes, and permissions follow what is already set: whoever may not open a folder gets no answer from it through Copilot either.

That last point is also the trap. If your shared folders are too open, Copilot finds things not meant for everyone, such as a payroll file in a folder called "General". Tidy your permissions before you roll Copilot out.

Start with Copilot Chat, already in your licence. Your team learns to write prompts at no extra cost. Buy the paid licence first for the people who sit in mail and meetings all day: that is where it saves the most time.

ChatGPT wins if you want a separate workspace

If you work in Google Workspace, in a mix of tools or mostly in an industry package, Copilot brings less. ChatGPT works apart from your software and is strong at work not tied to a program: rewriting a quote, explaining an export from your accounting, images for a post, a first draft of a job ad. With projects you keep files and instructions per client or theme together. For quotes, start from a fixed structure such as our quote template and let the assistant write the description, never the price.

The downside: you bring your work to the assistant yourself. What is not uploaded or connected, it does not know. And without agreements staff paste everything in, customer data included. So set down which tool, which plan and which data never.

Which to choose? By situation

How to roll it out without wasting money

1. Pick two or three tasks that cost your team time every week: summarising mail, writing quotes, meeting notes.
2. Start with what is free. Copilot Chat is in your licence; ChatGPT Business you can take monthly for a few people first.
3. Give five to ten people a paid licence for six weeks and measure the time before and after.
4. Make agreements on which data may go in and who reads every text back. In the EU, the AI Act has required you to support your people's AI literacy since 2 February 2025.
5. Extend to those who really use it. A licence nobody opens after six weeks, you cancel.

When an assistant on your own documents returns more

Copilot and ChatGPT are general assistants. They get weak as soon as the question lives in your own documents: "what is our price for an eight square metre bathroom", "which procedure applies to a damage claim", "what is in this customer's contract". Then you want an assistant that answers from your own procedures, price lists and files, with permissions per person and a source with every answer.

You can have that built, inside your own platform or client portal. If you want AI to act as well, such as putting an enquiry into your CRM or preparing a reply, that is AI automation; what an agent adds is in AI agents explained. Which kind of tool fits which task: AI tools for business. What such a solution costs per use, work out with the AI cost calculator.