We train Chicago teams on all four of these tools, usually on whatever accounts the company already pays for. That means we have no reason to push one over another, and we see the same question in almost every first call: "Which one should we standardize on?" This article is our answer for a typical 20-person company: an office manager, a few people in sales, operations and finance, an owner who wants to see the numbers, and nobody whose full-time job is IT.
Every price and data-handling statement below comes from the vendor's own pricing page, help center or documentation, checked in November 2026. AI pricing has changed several times this year, so treat the figures as a snapshot and confirm them before you buy.
Which AI assistant is best for a small business?
The best AI assistant for most small businesses is the one that fits where their files and email already live, bought on a business plan rather than personal accounts. The model quality gap between the four is smaller than the gap between a team that has been trained and one that has not.
In practice that gives a short decision rule. If your company runs on Google Workspace Business Standard or higher, start with Gemini, because you already pay for it. If you run on Microsoft 365 and live in Outlook and Teams, Copilot Business is the natural add-on, provided your SharePoint permissions are in order. If you want a general-purpose assistant that works the same way for everyone, regardless of email platform, ChatGPT Business or Claude Team are the two to compare. Many small teams end up with one of those two plus the assistant bundled in their office suite.
How much do ChatGPT, Copilot, Gemini and Claude cost for a 20-person team?
On annual billing, ChatGPT Business and Claude Team list at $20 per seat per month, Microsoft 365 Copilot Business at $21 on top of a Microsoft 365 plan, and Gemini comes included in Google Workspace Business Standard at $14 per user per month. The table shows the business tier of each.
| Tool | Business plan | List price per user per month | Seats | 20 seats, annual list |
|---|---|---|---|---|
| ChatGPT | ChatGPT Business, Standard seat (Premium seats for heavy users) | $20 annual, $25 monthly; Premium $100 annual, $125 monthly | 2 to 200 | About $400 a month |
| Claude | Claude Team, Standard seat (Premium seats for heavy users) | $20 annual, $25 monthly; Premium $100 annual, $125 monthly | 2 to 150 | About $400 a month |
| Gemini | Included in Google Workspace Business Standard and Plus (limited in Business Starter) | Workspace Business Standard $14 annual, $16.80 flexible | Up to 300 | No extra cost if you are already on Business Standard |
| Microsoft 365 Copilot | Copilot Business add-on to Microsoft 365 Business Basic, Standard or Premium | $21 annual, $25.20 monthly, plus the Microsoft 365 plan (Business Standard is $14 annual) | Fewer than 300 | About $420 a month on top of Microsoft 365 |
A few details change the math. Microsoft is running a first-year promotion that takes annual Copilot Business to $18 for existing customers with an eligible plan, available between July 1 and December 31, 2026. Microsoft also raised Business Standard from $12.50 to $14 on July 1, 2026. Google's Business Starter plan at $7 includes the Gemini app but only limited Gemini inside Gmail and the other apps; the full set (Docs, Sheets, Slides, Drive, Meet) starts at Business Standard. And eligible Microsoft 365 business plans include the free Copilot Chat, which answers from the web and from files you hand it; only the paid Copilot license works across your own mail, files and meetings.
Premium seats on ChatGPT and Claude cost five times as much because they carry roughly five times the usage. For a 20-person office, two or three heavy users on Premium and everyone else on Standard is a common pattern. Start everyone on Standard and move people up only when they hit limits.
Which AI tools keep company data out of model training?
All four vendors say their business plans do not use your company's prompts and files to train models by default. The risk for a small business sits in the personal accounts staff already use, where the defaults are different.
| Tool | Business plan: training on your data | Admin controls on the small-business tier | Personal plans |
|---|---|---|---|
| ChatGPT | "No training on your business data by default" | Admin console, SAML SSO, MFA | On Free, Plus and Pro, data sharing is on by default; users can turn off "Improve the model for everyone" |
| Claude | Model training "none by default" | SSO, domain verification, central billing, connector controls; SCIM and audit logs only on Enterprise | On Free, Pro and Max, each user chooses whether chats may be used for training |
| Gemini | Prompts, Workspace content and responses not used to train generative AI models without permission | Google Workspace admin console and its AI settings | With Keep Activity on, chats are used to improve Google services, including training, and a subset is read by human reviewers |
| Copilot | Prompts, responses and Microsoft Graph data not used to train foundation models | Microsoft 365 permissions, sensitivity labels, retention policies and audit apply | Enterprise data protection covers work accounts used by organizations, not personal Microsoft accounts |
Two practical consequences. First, the business plan is the control: once everyone signs in with a work account, you can turn people off when they leave, see usage, and rely on the vendor's business terms. Second, buying the business plan does nothing about the personal ChatGPT or Gemini account an employee opened last year. Microsoft's 2024 Work Trend Index found that 78% of AI users were bringing their own AI tools to work. Our guide to shadow IT and shadow AI covers how to bring that into the open without a fight, and the free AI acceptable use policy template gives you the written rule.
Copilot deserves one extra warning. Because it can see everything a user can open in SharePoint, OneDrive and Teams, a folder shared with "Everyone" years ago becomes searchable in seconds. Run a permissions check before you assign licenses. Our Microsoft Copilot guide for small business walks through it.
Where does each tool fit best?
Each tool has a home turf. These notes come from what we see in training rooms, so treat them as one practitioner's view, not a benchmark.
ChatGPT Business
ChatGPT is the assistant most employees have already tried, which shortens the learning curve. It works the same whether the company uses Outlook or Gmail, handles writing, analysis of uploaded spreadsheets and research well, and its Projects feature lets a team keep instructions and reference files together for recurring work. It is our default training platform because it runs on any plan. The trade-off is that it sits outside your email and file system unless you connect them, so people paste or upload more.
Microsoft 365 Copilot
Copilot's strength is location. It drafts in Outlook, recaps Teams meetings, and works on Word, Excel and PowerPoint files without copying anything into a separate tool. For an office that already spends its day in Microsoft 365, that removes friction. The cost is preparation: licenses, a SharePoint permissions review, sensitivity labels and Teams transcription all need attention first.
Gemini in Google Workspace
For a Workspace company, Gemini is the cheapest decision because it is already in the bill from Business Standard up. It works inside Gmail, Docs, Sheets, Drive and Meet, and Google says Workspace content is not used to train its models without permission. If you are on Business Starter, check what is limited before you plan training around it.
Claude Team
Claude tends to win with teams that work through long documents: contracts, policies, reports, proposals. Its Projects keep instructions and files for a recurring task in one place, and the Team plan now includes Claude for Microsoft 365, connectors, Claude Code and Claude Cowork. Smaller offices like that the Team plan starts at two seats.
Should a small business pay for more than one AI tool?
Usually not at first. Pick one assistant as the company standard, train everyone on it, and write the policy around it. A second tool makes sense later for a specific group, such as a finance lead who needs Copilot in Excel while everyone else uses ChatGPT.
The cost of two tools is rarely the licenses. It is two sets of rules, two places where saved instructions live, and two things to train on. If you do run two, keep one acceptable-use policy that names both and one shared prompt library.
How should a 20-person company choose?
Run a short, structured trial instead of reading reviews. This is the process we suggest in first calls:
- Write down where work lives. Email platform, file storage, the two or three systems people use all day. This usually eliminates one or two options immediately.
- List five real tasks per role. A proposal draft, a meeting recap, a spreadsheet clean-up, a customer reply, a policy question. Use the tasks, not the tool's demo.
- Pick a pilot group of three to five people across roles, on the business plan of each tool you are testing, never on personal accounts.
- Run the same tasks on each tool for two weeks, using practice or non-sensitive data, and record which output needed the least fixing.
- Check the admin side: SSO, removing a user, usage reports, where data is stored, and the vendor's business terms.
- Decide, write the one-page policy, then train. Rolling out without training is how companies end up paying for seats nobody opens.
Do Illinois rules change which AI tool you can use?
No Illinois law picks a tool for you, but some uses carry duties whichever assistant you choose. Since January 1, 2026, the Illinois Human Rights Act (as amended by HB 3773) bars employers from using AI in hiring, promotion, discipline and similar decisions in a way that discriminates, and requires notice to employees when AI is used for those purposes. If anyone in your office will use ChatGPT, Copilot, Gemini or Claude to screen résumés or evaluate staff, read our Illinois AI employment notice kit first. This is general information, not legal advice.
Can 312 train our team on whichever tool we pick?
Yes. Our training runs on your team's own accounts: ChatGPT on any plan by default, or Microsoft 365 Copilot, Claude or Gemini if that is what you pay for. Day 1 covers how these tools work, prompting, checking output and privacy; Day 2 builds labs on your own processes with practice data. We run sessions on-site across Chicago and the suburbs, from the Loop to Evanston, Oak Brook and Schaumburg, and live online for teams anywhere. A 2–3 hour workshop for up to about 15 people typically starts from about $2,500; longer programs are quoted in writing after a free first call. The AI training cost guide has the details, and Illinois employers may recover part of the cost through ETIP, explained in funding AI training in Illinois. For a ChatGPT-specific session, see ChatGPT training in Chicago.