Microsoft Copilot vs ChatGPT Enterprise vs Gemini vs Claude: Choosing a Workplace AI Assistant
For most large organisations the workplace AI assistant decision has already been half made by the productivity suite they run. The other half, how many seats, for whom, on what terms and with which data exposed, is where the money and the risk sit. Here is the honest comparison.
Your productivity suite usually decides the default, and seat discipline decides the cost. Microsoft Copilot fits organisations on Microsoft 365, works with your Microsoft data and is licensed per user on top of your plan. Gemini comes bundled into Google Workspace business plans. ChatGPT Enterprise and Anthropic's Claude are the leading standalone assistants, bought alongside either suite, and Claude also runs inside Copilot as one of its model providers. All four commit not to train their models on your business data by default. The bigger risks are seats nobody uses and assistants that surface documents people should never have been able to see.
C4C is an independent technology consultancy that helps organisations buy and govern AI without overpaying. We spent years on the vendor side building enterprise software quotes, so we know how these licences are priced, where the room is and which terms matter. Send us your situation and we will give you a straight view.
How they compare
| Microsoft Copilot | ChatGPT Enterprise | Gemini for Workspace | Claude | |
|---|---|---|---|---|
| Best fit | Organisations on Microsoft 365 | Teams wanting the leading standalone assistant, alongside either suite | Organisations on Google Workspace | Teams wanting a standalone assistant, including software teams using Claude Code, alongside either suite |
| How it is licensed | Paid add on per user over a qualifying Microsoft 365 plan; included in Microsoft 365 E7. Web based Copilot Chat is included at no extra cost | Negotiated per seat; no published price | Included in Workspace Business Standard and above | Team plan priced per seat publicly; Enterprise is a per seat fee plus usage at API rates |
| Works with your data | Grounded in Microsoft 365 data the user can access | Through connectors to your systems | Grounded in Workspace content the user can access | Through connectors to Microsoft 365, Google Workspace, Slack and more |
| Training on your data | Microsoft commits not to | OpenAI commits not to by default | Google commits not to | Anthropic commits not to by default |
| Watch for | Licences bought for everyone and used by few; oversharing in SharePoint | Running a second assistant beside the one in your suite | Assuming bundled means free of governance work | Forecasting usage based Enterprise costs; where UK data is processed |
Sources: Microsoft, Copilot licence options; Microsoft, enterprise data protection in Copilot; OpenAI, enterprise privacy commitments; Google Workspace, AI in Workspace plans; Anthropic, Claude plans and pricing; Anthropic, Claude Enterprise.
The honest read on each
Microsoft Copilot
Microsoft has renamed Microsoft 365 Copilot to Microsoft Copilot. Its strength is that it works inside the tools your people already use, grounded in the email, files, meetings and chats they can already access, under the same contractual data protection as the rest of Microsoft 365. Two licensing points matter. Web based Copilot Chat is included with eligible Microsoft 365 plans, so everyone can have a capable assistant without a new licence, while chat grounded in your organisation's data needs the paid Copilot licence. And Copilot now uses models from more than one provider: Microsoft notes that Anthropic models are currently excluded from its EU Data Boundary, which matters if you rely on that commitment. Microsoft, Copilot licence options; Microsoft, enterprise data protection in Copilot.
ChatGPT Enterprise
ChatGPT is the assistant many staff already use at home, which drives both demand and the shadow AI problem. The Enterprise edition adds administration, single sign on and connectors to company systems, and OpenAI commits not to train on business data by default. OpenAI, enterprise privacy commitments. There is no published price, so the deal is negotiated on seat count, term and options such as data residency. Check which residency regions are available for your contract rather than assuming. Its main cost risk in a Microsoft or Google estate is paying for two assistants for the same people.
Gemini for Google Workspace
Google includes Gemini in Workspace Business Standard and higher plans, with the Gemini app, AI inside Gmail, Docs and Sheets, and notebook and meeting features, while Enterprise plans add agent management and stronger data controls. Google says company data is not used for model training or ads, and that Gemini only retrieves content the user already has access to. Google Workspace, AI in Workspace plans. For a Workspace estate that makes Gemini the obvious default, and the cost question shifts to which Workspace plan you need rather than a separate AI licence.
Claude
Claude is Anthropic's assistant and, like ChatGPT, is bought as a standalone product alongside your suite. Its Team plan has a published per seat price, while Enterprise adds usage charged at API rates to the seat fee, which needs forecasting. Enterprise includes single sign on, audit logs, custom data retention and connectors to Microsoft 365, Google Workspace and Slack, and Anthropic commits not to train on your data by default. Anthropic, Claude plans and pricing; Anthropic, Claude Enterprise. Its enterprise page offers US only inference as an option but does not describe UK or EU processing, so check where your data will be handled. Claude also runs inside Copilot as one of Microsoft's model providers.
An assistant that respects your permissions will surface everything those permissions allow. Each of these assistants grounds answers in content the user can already reach, through the suite or through connectors, so years of overshared folders and sites become searchable in seconds. Fix permissions and labelling on the most sensitive content before a broad rollout, not after. Our guide to securing enterprise AI covers the controls.
Where the money goes: seats nobody uses
The commonest overspend is not the price per seat, it is the number of seats. Licences bought for every employee in a single tranche, then used regularly by a minority, turn into shelfware within a year. Start with the teams whose work clearly benefits, measure real usage, and expand on evidence. Our Copilot shelfware calculator puts a number on the gap if you have already bought.
How they are bought, and what to weigh
- Ramp, not big bang. Negotiate a phased rollout with the right to add seats at the same price, rather than committing every seat on day one.
- True down rights. Ask for the ability to reduce seats at renewal if usage does not materialise.
- Usage based pricing. Where part of the price is usage, as with Claude Enterprise, agree forecasts, caps and reporting before rollout so the bill does not surprise finance.
- Pilot terms that convert fairly. A pilot priced to win the deal can set an anchor you regret later, so agree how pilot pricing carries into the full contract.
- One assistant or two. If a team genuinely needs ChatGPT or Claude alongside Copilot or Gemini, license that team, not the organisation.
The wider disciplines are in our guide to negotiating the AI purchase.
Our position
We do not sell any of these assistants. Our job is to help you choose the right one for each part of the organisation, buy the number of seats you will actually use on terms that let you adjust, and put the permissions and governance in place before the assistant finds what it should not.
Deciding on Copilot, ChatGPT, Gemini or Claude?
Tell us which suite you run, how many people you are thinking of licensing, and any quote you have. We will tell you which assistant fits where, how many seats you really need, and which terms to push for. We spent years on the vendor side building quotes like these.
Prefer email? Reach us directly at hello@c4cgroup.co.uk.
Frequently asked questions
Is Microsoft Copilot better than ChatGPT Enterprise?
For organisations on Microsoft 365, Copilot is usually the better default because it works inside Outlook, Teams, Word and SharePoint and is grounded in data people can already access. ChatGPT Enterprise is a strong standalone assistant and suits teams with specific needs. Many organisations use Copilot widely and license ChatGPT Enterprise only for the teams that clearly benefit.
Is Gemini included in Google Workspace?
Yes. Google includes Gemini in Workspace Business Standard and higher plans, covering the Gemini app and AI inside Gmail, Docs, Sheets and other apps. Enterprise plans add agent management and stronger data controls. For Workspace customers the decision is mainly which plan you need rather than a separate AI licence.
Do Copilot, ChatGPT Enterprise, Gemini and Claude train on our data?
Each vendor commits not to. Microsoft says prompts, responses and data accessed through Microsoft Graph are not used to train foundation models. OpenAI commits not to train on ChatGPT Enterprise business data by default. Google says Workspace company data is not used for model training or ads. Anthropic says inputs and outputs on its business plans are not used for training by default. Check the commitments in your own contract.
Should we consider Claude for business use?
Yes, as one of the standalone assistants alongside ChatGPT Enterprise. Claude offers Team and Enterprise plans with single sign on, audit logs and connectors to Microsoft 365 and Google Workspace, and Claude Code for software teams. Note that Enterprise pricing includes usage at API rates, and check where your data will be processed if UK or EU location matters.
Is Copilot Chat free?
Web based Copilot Chat, which answers from the internet, is included with eligible Microsoft 365 subscriptions at no extra cost. Chat grounded in your organisation's own data, such as email and files, requires the paid Microsoft Copilot licence.
How do we avoid paying for unused AI seats?
Roll out in phases to the teams that clearly benefit, measure real usage, and expand on evidence. Negotiate the right to add seats at the same price and to reduce seats at renewal. If you have already bought, measure usage per seat and reclaim or reassign licences that are not being used.