AI and Privacy: What Happens to Your Data When You Use AI Tools

Millions of people in the UK now use AI tools daily — for writing, coding, research, customer service, and creative work. ChatGPT crossed 100 million weekly users globally within two months of its launch in late 2022. But most people have little idea what happens to the information they type into these systems. Do AI companies read your conversations? Is your data used to train future models? Can it be shared with third parties? This article explains what major AI platforms actually do with your data, what UK law requires of them, and how to protect your privacy when using these tools.

What Data Do AI Tools Collect?

When you use an AI tool like ChatGPT, Claude, Gemini, or Microsoft Copilot, several types of data are typically collected. The most obvious is the content of your conversations — the prompts you submit and the responses you receive. But most services also collect metadata: your IP address, device type, browser, timestamps, and session duration. Some platforms link this data to your account if you are signed in, and may retain it indefinitely unless you take active steps to delete it.

OpenAI’s privacy policy, as of June 2026, states that it collects usage data including conversation content, which it uses to train its models unless you opt out or use its enterprise tier. Anthropic collects conversation content in its consumer Claude product but provides enterprise customers with a data agreement under which conversations are not used for training. Google’s Gemini collects conversation data and, for users of the free service, may allow human reviewers to read a sample of conversations for quality assurance purposes. Microsoft Copilot, integrated into Office 365, operates under Microsoft’s enterprise privacy agreements, which are generally considered among the strongest in the industry for business customers.

Where Does Your Data Go?

Data entered into AI tools typically travels to data centres operated by the AI provider, which may be located outside the UK. OpenAI’s primary infrastructure is hosted on Microsoft Azure, with data centres across the United States and Europe. Anthropic uses Amazon Web Services infrastructure, with European region options available to enterprise customers. The location of data processing matters for UK legal purposes because it determines which data protection laws apply and what international transfer mechanisms must be in place.

Under the UK GDPR, personal data transferred outside the UK to countries without an adequacy decision requires additional safeguards. The UK has its own adequacy decisions and an International Data Transfer Agreement (IDTA) framework for transfers to countries without adequacy status, including many AI infrastructure providers operating in the United States. Most major AI providers have legal mechanisms in place for UK transfers, but the quality of those mechanisms varies and has been the subject of ongoing scrutiny by the Information Commissioner’s Office.

How AI Companies Use Your Data

AI companies use conversation data in several commercially significant ways. The most important is model training — using real user interactions to improve future versions of the model. This can genuinely benefit users, as models trained on real conversations learn to handle genuine use cases better than those trained only on curated datasets. But it raises significant privacy concerns when users share sensitive information in the belief it is private.

In 2023, Samsung engineers using ChatGPT to help debug code accidentally submitted proprietary source code and internal meeting notes. The data entered OpenAI’s training pipeline before Samsung’s IT department became aware. Samsung subsequently banned the use of external AI tools on company devices. Similar incidents have been reported at law firms where associates submitted confidential client information, and at healthcare organisations where employees used AI to draft communications about named patients.

Most consumer AI services allow you to opt out of having your data used for training, though this option is often buried in settings menus and is not enabled by default. OpenAI requires users to navigate to data controls to disable training use. Anthropic’s Claude app has a similar opt-out. Google’s Gemini includes a toggle in the My Activity settings. For most users, the default is that their data is used.

The UK Legal Framework

UK data protection law places obligations on AI companies processing UK residents’ personal data, regardless of where those companies are based. The UK GDPR and Data Protection Act 2018 apply to any organisation that processes personal data of UK residents, even if the organisation itself is not located in the UK.

Key rights under UK GDPR that are directly relevant to AI tool use include: the right to know how your data is processed (the transparency principle); the right to access your data; the right to have your data erased under the right to be forgotten; and the right not to be subject to solely automated decisions with significant effects on you. AI companies must provide a lawful basis for processing your personal data — for consumer services this is typically either consent (for marketing) or legitimate interests (for service operation and model training).

The ICO has been actively scrutinising AI data practices. In 2024, it issued a reprimand to a UK company that had deployed AI tools without conducting a Data Protection Impact Assessment (DPIA). The ICO has stated publicly that organisations using generative AI tools to process personal data must understand how those tools handle data — including whether data is retained for training — before deploying them in any customer-facing context.

Privacy Risks in AI Tools

Beyond data retention, several specific privacy risks are worth understanding when using AI tools.

Inference from limited data is one of the subtlest risks. Even if you do not share obviously personal information, AI systems can infer characteristics from your writing style, vocabulary, topic preferences, and interaction patterns. A 2024 MIT study found that a language model could infer demographic characteristics including approximate age, gender, and educational level from short text samples with accuracy significantly above chance. This means that even a notionally anonymous conversation may carry identifying information that users have not consciously shared.

Data breach risk is also relevant. AI providers store large volumes of conversation data, making them attractive targets for attackers. ChatGPT suffered a data breach in March 2023 in which some users’ payment information and conversation titles were temporarily exposed to other users. While OpenAI resolved the issue quickly, it illustrated that conversation data is not inherently protected from exposure events. As AI tools grow in popularity, their data stores become increasingly valuable targets.

Model memorisation is a more technical risk: AI models can, under certain conditions, reproduce verbatim content from their training data. Research in 2023 demonstrated that GPT-3.5 could be prompted to reproduce training data fragments that included personally identifiable information. This is a risk for individuals whose personal information appeared in publicly available text that was included in training datasets.

Workplace AI and Employee Privacy

For employees, AI tool use at work raises additional privacy considerations that go beyond the consumer context. UK employment law does not specifically address AI tool use, but the general framework of employment rights applies. Employers who monitor employee AI usage — for example, logging which prompts employees submit to AI tools — must comply with UK GDPR’s requirements for transparency, proportionality, and purpose limitation.

The ICO’s Employment Practices Code requires employers to inform employees that their computer usage is monitored, including any AI tools installed on company systems. Workers retain data protection rights even when using company equipment. Any employer deploying AI tools that process employee personal data — such as AI-powered performance monitoring systems that track productivity metrics — must conduct a Data Protection Impact Assessment before doing so.

The TUC and several UK unions have called for mandatory consultation with worker representatives before AI systems are deployed in workplaces. While this is not yet a legal requirement, the UK government’s approach to workplace AI regulation has been moving toward stronger guidance on worker rights in AI-affected employment contexts. Several large UK employers including BT, Lloyds Banking Group, and Vodafone have adopted voluntary AI use policies negotiated with union representatives.

What You Can Do to Protect Your Privacy

There are practical steps you can take to protect your privacy when using AI tools, regardless of which platform you use.

Opt out of training data use wherever possible. Log in to the settings of any AI tool you use regularly and find the training data opt-out. For ChatGPT this is in Settings > Data Controls > Improve the model for everyone. For Anthropic’s Claude it is in Privacy Settings. For Google Gemini it is in My Activity > Other Google Activity > Gemini Apps Activity.

Avoid inputting genuinely sensitive information. Do not paste real personal data, client or patient information, confidential business details, passwords, or health information into general-purpose AI tools. If your work requires AI assistance with sensitive data, use an enterprise-tier product with appropriate contractual data protections and a data processing agreement in place.

Use incognito or temporary sessions where available. Some AI tools offer guest or temporary sessions that are handled differently from logged-in sessions. Anthropic has stated that anonymous Claude sessions are not used for model training in the same way as logged-in sessions.

Read the privacy policy before using any new AI tool for work purposes. Pay particular attention to data retention periods, data sharing with third parties, and the legal basis for training data use. If a service cannot clearly answer these questions, treat it with caution.

What This Means for UK Users

AI tools are genuinely useful, and avoiding them entirely is not a practical approach for most people in 2026. The more realistic response is to use them thoughtfully. Understand that the free tier of most AI services typically involves an implicit exchange — your interaction data helps improve the product. Enterprise and professional tiers generally offer stronger privacy protections, which is a significant part of why they cost substantially more.

For businesses, the implications are more serious. Any UK organisation using AI tools to process customer or employee personal data must ensure the processing has a lawful basis, that appropriate data transfer mechanisms are in place if data leaves the UK, and that a Data Protection Impact Assessment has been completed where processing is likely to result in high risk to individuals. Failure to meet these requirements risks ICO enforcement action — the ICO has issued fines under the UK GDPR ranging from £50,000 to several million pounds — as well as reputational damage if a data incident involving AI-processed information becomes public.

The UK’s approach to AI and data privacy is still developing. The ICO issued its first detailed AI guidance in March 2024 covering generative AI data scraping, data subject rights in AI contexts, and the conditions under which legitimate interests applies to AI training. More sector-specific guidance is expected through 2026 and 2027. Staying informed about how your data is used — and actively exercising the rights UK GDPR gives you — is the most effective privacy protection available to individuals using AI tools right now.

This article is for educational purposes only and does not constitute financial advice.