In short
- Both tools are meant for business. According to the vendors, business data is not used to train the models by default.
- Microsoft Copilot (formerly Microsoft 365 Copilot) works inside Microsoft’s applications and accesses content the user is allowed to see anyway.
- ChatGPT Business and Enterprise are separate workspaces with administration, sign-in via SAML SSO and connected apps.
- For fixed processes with your systems, a chat assistant is not enough. Automation and agents come in for that.
The differences at a glance
The information comes from the vendors’ documentation (as of October 2026). Features and names change quickly, so check the current version before you decide.
| Question | Microsoft Copilot | ChatGPT Business and Enterprise |
|---|---|---|
| Where do users work? | In Microsoft 365 applications such as Word, Excel, Outlook and Teams, and in Copilot Chat | In a separate workspace for the team |
| What data does it know? | Content in Microsoft 365 such as emails, chats, documents and calendars, as far as the user has access | What users enter and upload, plus data from connected apps, respecting existing permissions |
| Permissions | Takes over the permissions from Microsoft 365 | Administrators control access and features, sign-in via SAML SSO |
| Data protection per vendor | Prompts, responses and data from Microsoft Graph do not train foundation models. GDPR commitments and EU Data Boundary | No training on business data without consent. Data processing agreement available. Storage in Europe for new Enterprise workspaces |
| Administration | Microsoft 365 admin center, Purview for retention and search | Administration in the workspace, conversation logs via the Compliance API in Enterprise |
| Extensions | Agents and connectors that administrators approve | Apps and custom GPTs in the workspace, controllable by administrators |
What matters in practice
- Tidy up permissions: Copilot shows only content users have access to. Microsoft itself points out that permissions in places such as SharePoint need to be right. If they are too generous, Copilot also finds what was not meant for everyone.
- Check the data location precisely: Microsoft cites the EU Data Boundary for Copilot but currently excludes models from Anthropic from it. OpenAI offers data storage in Europe for new Enterprise workspaces. Clarify location, retention period and sub-processors.
- Check extensions: Every connected app and every agent accesses data. At Microsoft as at OpenAI, administrators decide which extensions are allowed. Microsoft advises checking an agent’s privacy statement and terms of use before it sees company data.
- Plan costs realistically: Check the licence model and prices with the vendor and budget only for people who really need the tool.
- Set rules: An AI policy says which data may go into which tool and that private accounts are off limits for company data. For how the team handles it, the duty of AI literacy applies.
When which tool fits
- Microsoft Copilot: Your business uses Microsoft 365 throughout, documents sit in SharePoint and OneDrive, and Outlook and Teams shape the day.
- ChatGPT Business or Enterprise: Your team works a lot with text, research and analysis without being tied to an office suite, or you want to connect different sources. How to roll it out is covered in the article ChatGPT for business.
- Both: This happens, for example Copilot for work in Microsoft documents and ChatGPT for research. Then you need clear rules on which data may go where. If you use Google Workspace, check Google’s assistant Gemini against the same grid.
Where a chat assistant reaches its limits
An assistant helps with open tasks: drafting texts, summarising documents, answering questions about documents. It does not process cases by itself. If every incoming enquiry is to be checked, a quote prepared or an invoice matched, a fixed workflow is more reliable, cheaper per case and easier to control. That is where our AI automation and AI agents come in: they work with your systems, not next to them. We build such processes for businesses across the EU as specialists in AI implementation.
How to decide with a pilot
- Collect tasks: which five tasks per team cost the most time today?
- Clarify the data situation: where are the documents, and who may see what?
- Choose a pilot group: a small group from different departments, with clear rules.
- Measure: time saved, quality in samples, actual use.
- Decide: licences for the groups that benefit, and publish rules for everyone.
- Review regularly: models and features change quickly. Review the decision every six months.
Sources
- Microsoft: Data, Privacy, and Security for Microsoft Copilot, as of October 2026
- OpenAI: Enterprise privacy at OpenAI, as of 8 January 2026
- OpenAI: Introducing data residency in Europe, 5 February 2025, update of 16 January 2026
- Regulation (EU) 2016/679 (General Data Protection Regulation), Art. 28: EUR-Lex