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First-Party Data

First-Party Data

First-party data is information a business collects directly from its own audience through its own channels, such as website and app behaviour, purchase history, email engagement, form submissions and customer service records. The business owns it and knows exactly where it came from.

For years, advertisers relied heavily on data collected by others, such as third-party cookies and platform tracking across apps and websites. That data has become less reliable as browsers like Safari and Firefox block third-party cookies by default, Apple requires apps to ask permission before tracking, and privacy laws tighten. First-party data has become the most dependable foundation for targeting and measurement.

First-Party vs Zero-Party vs Third-Party Data

  • Zero-party data: information customers choose to tell you, such as preferences in a quiz or survey.
  • First-party data: information you collect from your own channels, such as purchases, site visits and email clicks.
  • Second-party data: another company's first-party data shared through a direct partnership.
  • Third-party data: information gathered by outside companies across many sites and sold or shared, the least transparent and most restricted type.

Examples of First-Party Data

  • Customer lists with emails and phone numbers, and their order history.
  • Website and app events, such as product views, add to carts and searches.
  • Email and SMS engagement from platforms like Klaviyo.
  • CRM records, sales call notes and support tickets.

How Marketers Use First-Party Data

  • Better ad optimisation: server side connections like Meta's Conversions API and Google's Enhanced Conversions send consented first-party data to ad platforms, improving tracking that browser pixels miss.
  • Audiences: customer lists for retargeting, exclusions and lookalike audiences.
  • Personalisation: product recommendations and email flows based on what each customer did.
  • Measurement: matching ad spend to real orders, supporting metrics like MER and LTV.

Collect It With Consent

First-party data is only an asset if it is collected and used lawfully. Be clear about what you collect and why, respect consent choices, and give people a reason to share, such as a useful newsletter, a loyalty programme or a quiz that improves recommendations. Vietnam's personal data protection rules, the GDPR in Europe and similar laws elsewhere all put consent and transparency at the centre.

Frequently asked questions

What is first-party data?+

First-party data is information a business collects directly from its own customers and channels, such as purchases, website behaviour, email engagement and form submissions.

What is the difference between first-party and third-party data?+

First-party data comes from your own relationship with customers. Third-party data is collected by outside companies across many sites, is less transparent, and is increasingly restricted by browsers and privacy laws.

Why is first-party data important for advertising?+

It keeps targeting and measurement working as third-party cookies and cross-app tracking decline, and it improves ad optimisation when shared with consent through tools like Meta's Conversions API.

Related terms

Attribution

Marketing Attribution

Marketing attribution is the process of assigning credit for a conversion to the marketing touchpoints that contributed to it. It answers which channels, campaigns, or interactions should be credited when a customer completes a purchase or a lead.

LTV

Customer Lifetime Value

LTV (Customer Lifetime Value, also written CLV) is the total revenue or profit a business expects to earn from a customer over the entire duration of the relationship, not just their first purchase.

Email Deliverability

Email Deliverability

Email deliverability is the ability of your emails to reach recipients' inboxes rather than being blocked or filtered into spam. It is distinct from delivery: an email can be delivered to a mail server yet still land in the spam folder, which counts as a deliverability failure.