Zero-party data

Zero-party data is information a customer intentionally and proactively shares with a brand, such as stated preferences, interests or communication choices.

Part of the Learn hub and the customer data glossary.

What it means in practice

Its value is accuracy and context. A customer who says "text me, not email" tells you more than a model can infer, and the exchange is easier to explain because the person sees why you asked.

It is still personal data once linked to an individual, so GDPR and similar laws apply and purpose limitation holds: preferences given to improve service are not automatically permission to profile for sales. Keep preferences and consent as separate records, because stating an interest is not agreeing to marketing about it. Stated health information is special-category data under GDPR Article 9 and may be protected health information when a covered entity holds it, so a stated interest in a condition deserves the same care as a diagnosis.

Example (health insurance): a member chooses text reminders for wellness programmes and no email in a preference centre. The platform stores the channel preference and the consent for each purpose separately, and does not infer a condition from which programmes the member selects.

Related terms

• First-party data: the observed counterpart.
• Third-party data: data from outside the relationship.
• Consent state: kept separate from preferences.
• Purpose limitation: limits reuse of declared data.
• Data minimisation: ask only what you will use.

Where it matters

• Zero-party, first-party and third-party data: definitions and what changes after cookies.
• Customer journey orchestration: using declared preferences safely.