Special‑Category Data: GDPR Duties & Handling Tips | Sprintlaw UK (2025)

If your business handles sensitive customer information-like health records, biometric scans, or details about someone’s beliefs-there’s a good chance you’re dealing with something called special category data under UK GDPR. If that phrase instantly fills you with a sense of legal dread, don’t stress! Special category data is a big compliance area, but with a clear understanding and some practical steps, you can protect your customers and your business from day one.

In this guide, we’ll break down what counts as special category data, why it matters, and what extra obligations UK businesses face. We’ll also share practical tips so you can handle these sensitive details the right way-and avoid those hefty fines or reputational headaches nobody wants.

Understanding Special Category Data

Let’s start with the basics: what is special category data?

Under the UK GDPR (General Data Protection Regulation) and the Data Protection Act, special category data refers to types of personal information considered extra sensitive by law. That means, if mishandled, the impact on someone’s privacy, rights or freedoms could be especially serious.

Special category data is a subset of personal data, but not all personal data makes the list. Regular things like names and addresses don’t qualify-unless they reveal something about a person’s private life that the law specifically wants to protect.

Why Special Category Data Requires Extra Protection

The reason this category exists is simple-some facts about us, if misused or leaked, carry much higher risks. Imagine an employer publicly revealing an employee’s health condition, or a lost laptop containing lists of a charity’s supporters by religion or political beliefs. Those situations can not only cause embarrassment or distress-they might even lead to discrimination, exploitation, or safety threats.

Because of these risks, the law says organisations must apply much stricter safeguards to special category data, above what’s needed for ordinary personal details. In practice, that means tougher rules for collecting, using, sharing, and storing this information.

Legal Framework: GDPR and the ICO

If your business is based in the UK-or you deal with UK customers-then the UK General Data Protection Regulation (GDPR) and the Data Protection Act 2018 set out your main rules for handling special category data.

The Information Commissioner’s Office (ICO) is the UK’s chief data privacy regulator. The ICO enforces GDPR rules, investigates breaches, and issues penalties when organisations fall short.

• The GDPR gives individuals strong control over their data, especially when it comes to sensitive or special category information.
• The ICO provides guidance (see: ICO’s website) and can impose fines or take legal action for breaches-so they’re worth listening to!

If you’re collecting or using any kind of personal data-be it a customer email list, employee records, or user analytics-you need to be GDPR compliant. But for special category data, the standards are even higher.

Examples: What Qualifies as Special Category Data?

So what counts as special category data under the GDPR? Here’s the official list:

• Racial or ethnic origin
• Political opinions
• Religious or philosophical beliefs
• Trade union membership
• Genetic data
• Biometric data (for uniquely identifying someone, e.g. fingerprint or facial scans)
• Health data (including mental and physical health, medical history, test results, disabilities, and related details)
• Sex life or sexual orientation

This means any data that would directly or indirectly reveal these details about a person falls under stricter rules-regardless of whether they’re a customer, staff member, supplier, or someone else connected to your business.

Common Special Category Data Examples

• Patient medical notes at a private clinic (health data)
• Staff ethnicity details in an HR file (racial origin)
• Trade union membership noted on payroll records
• Religious preference or dietary requirements collected for event catering
• Customer fingerprints or facial recognition scans for secure access

If you store or process this kind of data-even if just occasionally-it’s important to treat it as special category data for legal compliance.

Business Risks and Penalties

Let’s be honest: handling personal data always comes with responsibility, but getting special category data wrong can be especially damaging.

• Fines: For serious GDPR breaches involving special category data, the ICO can issue fines up to £17.5 million or 4% of your annual global turnover (whichever is higher).
• Reputational harm: News of poor data handling spreads quickly. Loss of trust can lead customers, partners, and staff to walk away.
• Legal action: Individuals affected by misuse or leaks can sue for compensation or damages, even if you only made a mistake.

And it doesn’t just affect big brands-small businesses can feel the impact just as much. The ICO has taken action against NHS trusts, charities, and local businesses for breaches regarding things like unauthorised access to medical files or failure to secure biometric data.

Core Business Duties for Special Category Data

If your business collects or processes special category data, you must comply with extra legal requirements on top of general GDPR duties. Here are the key things to know:

1. Only Process If You Have A Lawful Reason (Plus A Condition)

It’s not enough to just have a lawful basis (like consent or contract) for processing special category data. The GDPR says you also need to meet one of the specific conditions listed in Article 9, which are limited and tightly defined.

• The most common condition is explicit consent-this means the individual has clearly agreed, after being fully informed, for you to process their special category data.
• Other possible conditions include legal obligations in employment, vital interests (life-or-death situations), medical diagnosis, or reasons of public interest-each only applies in fairly narrow contexts.

Always check which condition applies before collecting or using special category data. If you can’t meet one, you shouldn’t process it at all.

2. Tell People What You’re Collecting (And Why)

Transparency is key. Your Privacy Policy must spell out:

• What special category data you collect
• Why you need it (the business reason)
• How it will be used
• Who it could be shared with
• How long it will be kept, and how it’s protected

Under UK GDPR, this isn’t optional. Customers, employees, and other individuals have the right to know and understand exactly how their sensitive info will be handled.

3. Keep Data Extra Secure

Special category data needs stronger security than ordinary details. This means robust technical measures (like end-to-end encryption, firewalls, and strong access controls) and organisational safeguards (training, locked cabinets, or limited access policies).

• Limit access to only those who strictly need it for work
• Use encryption, password protection, and regular security audits
• Have a plan for dealing with data breaches-including informing the ICO and affected individuals quickly

These steps are required by law. If you experience a breach involving special category data and can’t show you took reasonable security steps, the consequences are likely to be much more severe.

4. Minimise What You Collect & Store

Don’t keep more data than you need. Ask yourself-do you really need to know someone’s religion, ethnicity, or medical details? If not, don’t ask. If you do, make sure you’re clear about why and delete it when no longer needed.

Laws like the GDPR require you to practice data minimisation: collect only what’s essential, store it for only as long as necessary, and then securely delete it.

5. Maintain Detailed Records

If you process special category data, you must keep up-to-date records showing:

• What categories of special data you hold
• Where it’s stored and processed
• Your legal basis for processing it (including which condition you rely on)
• Security measures in place
• Any data sharing with third parties or overseas transfers

These records are essential if the ICO comes knocking, or if you ever need to prove compliance. If you’re just getting started, check out our Online Business Legal Requirements for more detail on the documentation side of compliance.

6. Carry Out A Data Protection Impact Assessment (DPIA)

Whenever you plan to process special category data at scale, or if the data could pose a high risk to individuals’ rights, you are required to carry out a Data Protection Impact Assessment (DPIA). This means proactively thinking through risks and showing you have measures in place to minimise harm.

Think of a DPIA as a risk assessment: it’s not just a box-ticking exercise-if you ever need to justify your processing, it’s your main evidence of careful planning.

Need help with this step? Our guide on Data Privacy Impact Assessments breaks it down further.

Best Practices For Compliant Handling Of Special Category Data

Laying strong legal foundations isn’t just about avoiding trouble-it’s a way to build customer trust and set your business up for long-term success. Here are some practical tips for businesses handling special category data:

• Review Your Data Flows: Map out what special category data you collect, and from whom. Check if you really need it, and whether you can rely on a GDPR condition for collecting it.
• Update Your Privacy Notices: Make sure your Privacy Policy is up-to-date and clearly explains special category data (not just “personal data” generally).
• Implement Access Controls: Limit access to sensitive data to the smallest possible group of people, and monitor who views or uses it.
• Train Your Team: Everyone handling special category information should know the importance, how to spot risks, and what to do if something goes wrong (e.g. reporting a suspected data breach).
• Secure Your Contracts: If you use third-party services (like payroll providers or cloud storage) to process special category data, make sure they have strong privacy and security standards in place. Use properly drafted Data Processing Agreements.
• Prepare For Data Subject Requests: Be ready to respond if someone asks to see, correct, or erase their special category data. Under GDPR, you must have clear processes for these requests, and act quickly.

If you’re not sure where to begin, or want to be confident you’re ticking all the legal boxes, consulting a privacy lawyer is a smart move. You can also check out our one-stop Privacy Policy (GDPR) service to get started.

Key Takeaways

• Special category data under the UK GDPR is personal information considered extra sensitive-think medical, biometric, ethnicity, religious, and similar details.
• Businesses must have BOTH a lawful basis (like explicit consent) AND meet a GDPR “condition” to process special category data.
• Failing to comply with special category data rules brings higher risks: tougher ICO action, big fines, legal claims, and lasting reputational damage.
• Key compliance steps include mapping your data, updating Privacy Policies, tightening security, training staff, limiting data collection, and keeping detailed records.
• Consider a Data Protection Impact Assessment when processing special category data at scale, or where there’s a high risk to individuals’ rights.
• For most businesses, early legal advice is an investment: it keeps you protected, compliant, and trusted by your customers from day one.

Still unsure if your business handles special category data-or want to double check your compliance? That’s where we can help. Reach out to Sprintlaw UK for a free, no-obligations chat at 08081347754 or [emailprotected]. We’re here to help you protect your business and your customers’ sensitive data, every step of the way!