Official documentation
What is special category data? (UK ICO guidance)
Information Commissioner's Office (UK), 2025
Read the originalRead on October 17, 2026
- What it is
- The UK data protection regulator's guidance on special category data, including what counts as biometric data and when it becomes special category data.
- How much weight it carries
- Official regulator guidance on the UK GDPR, which mirrors the EU GDPR on this point. Guidance is not binding law and courts can read the rules differently; the ICO notes that it is not a full statement of the law.
Facts taken from this source
- The UK data protection regulator says all biometric data is personal data, because it relates to an identified or identifiable person.
“All biometric data is personal data, as it relates to an identified or identifiable individual.” (What is biometric data?)
- The UK regulator says biometric data is special category data whenever it is processed for the purpose of uniquely identifying a natural person.
“Biometric data is also special category data whenever you process it “for the purpose of uniquely identifying a natural person”.” (What is biometric data?)
- The UK regulator lists voice recognition among the physical or physiological biometric identification techniques, alongside facial recognition and iris scanning.
“Examples of physical or physiological biometric identification techniques: facial recognition; fingerprint verification; iris scanning; retinal analysis; voice recognition; and ear shape recognition.” (What is biometric data?)