Copilot is the natural first test when the information sits in Microsoft 365. ChatGPT Business is worth testing alongside it when the hard part is drafting, analysing or comparing documents you choose to give it, such as two proposals.
Whichever you test, compare the whole task, from finding the information to checking the result. Take a weekly client update. Someone finds recent decisions, checks delivery dates, drafts the message and confirms the commitments before it goes out. The right tool depends on which of those steps takes the most effort.
Which to try for which job
| The work that needs help | Where to start | What would change the choice |
|---|---|---|
| Finding decisions in Microsoft email, meetings and files | Copilot, with access to your work data | If Copilot misses records you know exist, compare both on the same approved documents. |
| Comparing two proposals you can share as a small, approved set of documents | Test both on the same documents | One gives a more accurate comparison with less fixing |
| Pulling information from several business apps | Check the connections you need in both | A connection you need isn't available, or it gives access to more files than the task needs |
| Preparing a recommendation for a client | Either can draft it | The reviewer can't trace the conclusions back to evidence |
Check which Copilot you mean
This article compares Microsoft 365 Copilot, the business version used with a work account, with ChatGPT Business. OpenAI renamed ChatGPT Team to ChatGPT Business on August 29, 2025, so older articles may use the old name.
Your licence matters. Microsoft's guide to how Copilot finds information explains that without an add-on, Copilot answers from the web. Access to your business email, meetings and files comes with the paid add-on. Seeing a Copilot button doesn't mean the job you have in mind will work.
ChatGPT can also use connected apps. What's available, and what each app can do, depends on the app, your plan, your region and your workspace settings. Check the exact connection before you promise that either tool can put together the whole update.
Time the whole job, checking included
Use one finished client update as the test, with confidential details removed or approved for the trial. Give both tools the same source material and ask for the same result.
Ask each to list completed work, open decisions and the next commitment. Ask for a source for every date. Include one unresolved point on purpose and see whether the draft keeps it open.
Record the time spent gathering information, giving instructions, checking the answer and fixing it. Add any licence or connection changes each option needs, using current quotes, and the staff time to set it up. A polished draft can still take a long time to check, so score each draft by how quickly someone can confirm every claim.
Test the handoff too. Can the person who usually writes the update repeat the process without the owner explaining it again? Would the manager trust the sources enough to review it quickly?
What each vendor says about your data
Microsoft says data in its business Copilot is not used to train the underlying AI models. OpenAI says ChatGPT Business data is not used for training by default. Neither promise tells you how long data is kept, how connected apps handle it, or whether you may use a client's document at all.
Go through the client confidentiality checklist before the trial. Confirm the exact account, the information allowed, the connections and who reviews the result. Whichever vendor you choose, a business subscription doesn't on its own keep your data in Canada.
Next step
If you can't yet name the first task, try the free AI Opportunity Map. If Claude is also on your shortlist, read Copilot vs ChatGPT vs Claude: which is safer?
Sidekick helps you pick the task, choose the tool and put the new process to work. To talk it through, bring one recurring task and a description of the finished result. We'll look at where it gets stuck and what a useful trial would need to show.
Sources checked October 12 and 16, 2026. Microsoft privacy documentation updated August 18, 2026. Undated vendor pages describe the current service and may change.