ChatGPT Business vs Microsoft 365 Copilot pricing: what a seat actually costs on each

Short answer: Microsoft 365 Copilot Business is $18.00 per user per month paid yearly and a ChatGPT Business Standard seat is $20.00, so Microsoft looks cheaper by $2. It is not a like-for-like comparison. The Microsoft $18 is an add-on that assumes you already pay for a qualifying Microsoft 365 subscription underneath it. The OpenAI $20 is a standalone total. Compare all-in prices and it flips: Microsoft 365 Business Standard with Copilot is $23.50 against OpenAI's $20.

Last updated August 2026. OpenAI rates read off the ChatGPT pricing page with the Business and Enterprise tab open on August 29, 2026, served to a United States address. Microsoft rates read off the Microsoft 365 Copilot for Business page the same day. We sell a competing flat-rate product, so check the arithmetic rather than trusting it.

How much does ChatGPT Business cost compared to Microsoft 365 Copilot?

Both vendors sell seats, both quote a headline annual rate, and both have a second number they do not put on the card. OpenAI charges $20 per user per month for a ChatGPT Business Standard seat billed annually, rising to $25 if you pay monthly. Microsoft charges $18.00 per user per month for Microsoft 365 Copilot Business paid yearly, marked down on its own page from a listed $21.00.

On those two numbers alone Microsoft wins by $2 a seat, which is $1,200 a year across 50 people. That is the comparison almost every roundup runs, and it is the wrong one, because the two prices are not measuring the same thing.

ChatGPT Business vs Microsoft 365 Copilot pricing, side by side

Why the $18 and the $20 are not the same number

Microsoft 365 Copilot Business is an add-on. It layers onto a Microsoft 365 subscription you already hold, and it does very little without one, because the whole point of it is that it works inside Word, Excel, Outlook and Teams against your own tenant data. If you are not already a Microsoft 365 customer, $18 does not buy you a working product.

ChatGPT Business is standalone. There is nothing underneath it to buy. For $20 you get a workspace with SAML, SSO and MFA, centralized billing, usage analytics, spend controls, connectors to Google Workspace, Slack, GitHub and Microsoft 365, workspace agents, Codex, and a default that OpenAI does not train on your business data.

Microsoft publishes the honest all-in comparison itself, on the same page. Microsoft 365 Business Standard with Copilot is $23.50 per user per month paid yearly, and Business Premium with Copilot is $32.00. Those are the numbers to put next to OpenAI's $20 if you are pricing the whole stack rather than a marginal seat. Read that way, OpenAI is $3.50 a seat cheaper, not $2 more expensive, and the gap runs the opposite direction to the one most comparisons report.

Which is cheaper if you already pay for Microsoft 365?

Microsoft, clearly, and it is not close on price. If your company already runs on Microsoft 365, the marginal cost of adding Copilot is $18 a seat and nothing else changes. Adding ChatGPT Business instead costs $20 a seat on top of a Microsoft bill you are still paying in full, so your true incremental spend is $20 against $18 and you now administer two AI tools.

The argument for paying the extra $2 anyway is not about price. It is that the two products are good at different things. Copilot is strongest where the work already lives in Microsoft files and Teams threads, because the grounding is the product. ChatGPT is strongest as a general reasoning surface with a much larger ecosystem of connectors, and it ships Codex in the same seat. Plenty of companies end up buying both for different departments, which is a legitimate outcome but should be a decision rather than an accident.

Deciding which staff get which tool is a straightforward resource and capacity planning exercise, and it is worth doing before renewal rather than after: measure who actually uses what for a month, then allocate. Both vendors give you usage analytics in the admin console, so the data is there for free.

What about heavy users?

The two vendors solve this in opposite ways, and it is the biggest structural difference between them.

OpenAI sells a second seat type inside the same plan. A ChatGPT Business Premium seat is $100 per user per month billed annually, or $125 monthly, and OpenAI describes it as five times more usage than Standard with no five hour limit. You can mix Standard and Premium seats in one workspace, so the engineers and analysts who run out get upgraded individually while everyone else stays at $20. A 40 person company with 5 heavy users pays $1,200 a month rather than $800.

Microsoft does not sell a heavier Copilot seat. It sells you a meter instead. Building and running custom agents happens in Copilot Studio, which is billed in Copilot Credits at $0.008 each when you prepay a $200 pack of 25,000, or $0.01 on pay-as-you-go. That is a genuinely different financial shape: OpenAI's ceiling is a bigger fixed seat, Microsoft's is a variable bill that grows with usage and stops your agents entirely at 125 percent of prepaid capacity. We took that meter apart in Copilot Studio pricing, and the licensing routes into it in do you need a Copilot Studio license.

Does either price include a coding assistant?

OpenAI does, Microsoft does not. Codex is listed among the features included in every ChatGPT Business seat, at both Standard and Premium. Microsoft sells its coding assistant as a separate product, GitHub Copilot, priced at $0 for Free, $10 for Pro, $39 for Pro+ and $100 for Max per user per month.

For an engineering-heavy company that is a real line item rather than a rounding difference. Twenty developers on GitHub Copilot Pro is $200 a month on top of whatever you pay for Microsoft 365 Copilot, and the equivalent capability arrives inside the $20 ChatGPT Business seat. Whether Codex is as good as GitHub Copilot for your stack is a separate question worth testing on your own repositories, but the pricing asymmetry is unambiguous and it is routinely left out of comparisons.

What happens when you outgrow the published plans?

OpenAI stops at a headcount. ChatGPT Business is scoped to teams of 2 to 200 employees, so the 201st hire moves you to ChatGPT Enterprise, which publishes no price at all. The Enterprise card reads "Custom pricing" and links to a sales form. It adds SCIM, encryption key management, domain verification, role-based access control, custom data retention, data residency in ten regions, and a GPT Instant context window of 128K against 54K on Business. There is also a footnote worth reading twice: credit-based and token-based pricing are available on Enterprise plans, with no published rate for either. We set out everything OpenAI does and does not disclose in ChatGPT Enterprise pricing.

Microsoft has no equivalent ceiling, because it routes you upward through licence tiers you can price yourself. Microsoft 365 E3 is $39 per user per month, E5 is $60, and E7 is $99 with Copilot included in the seat. That last one matters for the arithmetic: the step from E5 at $60 to E7 at $99 is $39, against a $30 Copilot enterprise add-on bought separately, so the bundle costs $9 more and brings the rest of the E7 feature set with it. The full ladder is in Copilot license cost.

The practical difference is predictability. With Microsoft you can price your own future on a public page. With OpenAI, growth past 200 people means a negotiation whose starting point you cannot look up, and going into that conversation before you hit the ceiling is a materially stronger position than going into it after.

So which one should you buy?

Buy Microsoft 365 Copilot if your company already runs on Microsoft 365, most of the work lives in Office files and Teams, and you want the cheapest marginal seat. At $18 with the tenant grounding included it is the efficient answer, and your identity, admin and compliance story is already built.

Buy ChatGPT Business if you are not locked into Microsoft, if you want the cheapest published all-in seat at $20, if your engineers would otherwise need a separate coding assistant, or if you want the option to upgrade individual heavy users to a $100 Premium seat without moving anyone else. Commit annually unless your headcount is genuinely volatile, because monthly billing costs 25 percent more on both seat types.

Buy neither if what you actually wanted was the work finished rather than a faster way to do it yourself. Both of these products are chat windows with governance around them: somebody still has to open the tool, know what to ask, and check the output. That is a different purchase from an agent you brief once and leave to complete the job, and it is priced differently too. Ours is $149 a month flat, for the account rather than the person, which stops mattering how many people you hire. If you are running this comparison across more than two vendors, Gemini Enterprise pricing covers the Google side on the same basis.

Frequently asked questions

Is ChatGPT Business cheaper than Microsoft 365 Copilot?

It depends on what you already own. As a standalone purchase ChatGPT Business is cheaper at $20 per user per month against $23.50 for Microsoft 365 Business Standard with Copilot. As an add-on to an existing Microsoft 365 subscription, Microsoft is cheaper at $18.00 against $20.00. The two headline prices are not measuring the same thing.

How much is Microsoft 365 Copilot per user?

Microsoft 365 Copilot Business is $18.00 per user per month paid yearly, reduced on Microsoft's own page from a listed $21.00. It requires a qualifying Microsoft 365 subscription underneath. Bundled alternatives are $23.50 for Business Standard with Copilot and $32.00 for Business Premium with Copilot, both paid yearly.

How much is ChatGPT Business per user?

A Standard seat is $20 per user per month billed annually and $25 billed monthly. A Premium seat, which OpenAI describes as five times the usage with no five hour limit, is $100 billed annually and $125 monthly. Both seat types can be mixed inside one workspace, and the plan is scoped to teams of 2 to 200 employees.

Does ChatGPT Business include a coding assistant?

Yes. Codex is included in every ChatGPT Business seat at both Standard and Premium levels. Microsoft sells its equivalent separately as GitHub Copilot, at $10 per user per month for Pro, $39 for Pro+ and $100 for Max, on top of any Microsoft 365 Copilot licence.

Which is better for a company already using Microsoft 365?

Microsoft 365 Copilot, on cost and on integration. The marginal seat is $18, the grounding in your own Office and Teams content is the core of the product, and identity and compliance run through infrastructure you already operate. The case for adding ChatGPT Business on top is capability rather than price, particularly a larger connector ecosystem and Codex in the same seat.