In short (TL;DR)
Conversations in free and regular paid ChatGPT are used for model training by default: invoices, payroll data and client lists don’t belong there. Business tiers (ChatGPT Business and Enterprise, Claude for Work, Gemini inside Google Workspace) don’t train on your data, and that promise is contractual. Either way, GDPR responsibility stays with you, because accounting data is full of personal data. Three rules: use a business account, never put personal data into a free chatbot, and write down your company’s AI policy.
Does ChatGPT train on your data?
It depends on the account, and the difference isn’t fine print — it’s the whole deal:
| Tool | Free / regular account | Business account |
|---|---|---|
| ChatGPT | chats used for training by default (can be turned off) | Business and Enterprise don’t train on your data |
| Claude | consumer chats used for training by default (can be turned off) | Claude for Work and the API don’t train on your data |
| Gemini | consumer app activity can be used for training | Workspace data isn’t used for training (contractual commitment) |
OpenAI documents the business-tier principles on its enterprise privacy page, and Google’s Workspace commitment is part of its data processing addendum, as this overview explains. One nuance worth knowing: even business-tier content can be retained briefly for abuse monitoring, around 30 days at OpenAI. “No training” doesn’t mean “instantly deleted”.
Why is accounting data especially sensitive?
Because it’s packed with personal data. A sales invoice carries your customer’s name and contacts, a purchase invoice the supplier representative’s details, a payroll file names, IDs and bank accounts. Under GDPR you remain the controller no matter which tool the data flows into. Metomic’s 2026 guide puts it well: the real risk starts before the prompt, with the decision about what reaches the chat window at all.
A simple test: if you wouldn’t email the data to a stranger, don’t paste it into a free AI chat either.
What does GDPR require from you?
- A data processing agreement (DPA): if an AI tool processes personal data, you need a contract with the provider. Business tiers ship with one, free tiers don’t.
- Minimization: give the AI as little as the task needs. A posting suggestion doesn’t require your customer’s personal ID code.
- Transparency: if AI tools are part of your workflow, your privacy notice should say so.
- The right to erasure: you must be able to answer where a client’s data lives, including when it passed through an AI tool.
Practical rules for accountants
- Use a business account for work — the difference from a free account is contractual, not cosmetic.
- Never put personal data or bank details into a general-purpose AI chat, not even “just this once”.
- Strip or replace names and numbers when you ask an AI for advice based on an example.
- Write a short company AI policy: what’s allowed, what isn’t, and on which account.
- Prefer workflows where data stays inside your accounting system and the AI comes to the data, not the other way around. We cover this in our guide to AI accounting.
If you want an AI assistant to see your books in a controlled way, without pasting anything into a chat window, that’s exactly what MCP interfaces are for. We explain them in MCP for accounting AI assistants.
Summary
You can give accounting data to ChatGPT when you’re on a business tier that comes with a DPA and doesn’t train on your data. The free version is a training-data pipeline, and personal data must stay out of it. GDPR responsibility is yours in every scenario: minimize, anonymize and put your AI rules in writing. This is a general overview, not legal advice.
Try Bilnex’s free invoice processing, where your data stays inside the system.
FAQ
Does free ChatGPT use my data for training?
Yes — conversations on free and regular paid accounts are used for model training by default, though you can turn this off in settings. Business tiers (ChatGPT Business and Enterprise) don’t train on your data.
Which AI account is appropriate for company data?
A business tier that includes a data processing agreement and a no-training commitment: ChatGPT Business or Enterprise, Claude for Work, or Gemini as part of Google Workspace. Free accounts aren’t suitable for business data.
Can I paste anonymized data into a free AI chatbot?
Carefully, if at all. When names and numbers are replaced so no individual can be identified, the risk drops — but half-masked data (initials, a rare job title) still counts as personal data under GDPR. A business account is the safer route.
Does a business account mean my data is deleted immediately?
No. Business tiers don’t use your data for training, but content can be retained briefly for abuse monitoring — around 30 days at OpenAI. Check your provider’s contract for the exact retention terms.