ChatGPT vs Copilot vs Claude vs Gemini for B2B sellers
For most B2B sellers the best AI assistant is the one your company already provides: Microsoft Copilot if you work in Microsoft 365, Gemini if you work in Google Workspace. ChatGPT and Claude are excellent if your company allows them. All four can do the core sales jobs well once they know your work.
The short answer by situation
| Your situation | Start with |
|---|---|
| Your company uses Outlook, Teams and Microsoft 365 | Microsoft Copilot |
| Your company uses Gmail and Google Workspace | Gemini |
| Your company has approved ChatGPT or Claude | The approved one |
| You work for yourself and choose freely | Try ChatGPT or Claude for a week each |
What matters for sales work
- Access to your data. Copilot and Gemini sit inside the email and calendar you already use. ChatGPT and Claude can connect to email, calendar and CRMs through connectors, depending on your plan and your company's settings.
- Writing quality. All four write well. The difference you'll notice comes from how well you've described your style, not from the tool. See making AI write like you.
- Standing instructions. All four let you save instructions or a project so you don't repeat yourself.
- Data and privacy. Business and enterprise plans generally don't use your data to train models, while some consumer plans may unless you opt out. Check your plan's terms and your company's policy before pasting customer information.
Our honest view
The tool is the smaller decision. A seller with a well-briefed Copilot will get more done than a seller with a blank ChatGPT, and the other way round. Spend your first hour on the setup: your role, your accounts, your rules and your writing style. Then use AI for one job, such as meeting prep, every day for two weeks.
Don't run two tools in parallel at first. Pick one, set it up properly, and switch only if something important is missing.
When to switch
Switch if your current tool can't reach the data you need (for example your CRM), if your company changes its approved tools, or if you consistently need to rewrite its drafts even after setting up your style. Your setup (job description, rules, style) is plain text, so it moves with you.
Related guides
- AI for B2B sales: a beginner's guide
- How to make ChatGPT or Copilot write like you
- More copy-paste sales prompts
Want this set up for you?
FirstLight OS sets up the AI you already use (ChatGPT, Copilot, Claude or Gemini) with your job, your accounts and your writing style, and adds daily routines with an approval step before anything is sent. One-off payment, from €100.