First-Party vs Third-Party Data: A Guide for Publishers

First-party data is information a publisher or brand collects directly from its own audience on channels it owns, such as its website, apps, newsletters and CRM. Third-party data is collected by companies that have no direct relationship with the user, usually across many websites, and is then aggregated and sold or licensed to advertisers. In between sit second-party data, which is another company's first-party data shared with you through a direct partnership, and zero-party data, which users intentionally and proactively give you, such as preferences in a profile or answers to a survey.

The short answer for publishers: first-party data is more accurate, cheaper to use and under your control, but it is still personal data, so you need a lawful basis, usually consent, before you collect it and use it for advertising.

Data is the essence of mass personalisation and targeted marketing. Safari has blocked third-party cookies by default since 2020 and Firefox has isolated them with Total Cookie Protection by default since 2022. Google Chrome dropped its plan to remove third-party cookies, but cross-site tracking keeps getting less reliable, so first-party data with proper consent is pioneering the new way for marketing.

Marketers, publishers and brands are looking to improve on how they use first-party data, because of the ever evolving global data privacy laws and legislation.

There are new challenges for adapting to first-party data only in your digital marketing pipeline: how to collect first-party data, how to use, how to manage consent etc. The whole digital marketing ecosystem in the privacy age will be redefined.

Secure data, privacy and compliance by obtaining consent then respecting user’s preferences are the foundation of the new digital marketing world.

• First-Party vs Third-Party Data Comparison
• What Is First-Party Data?
  • Why Is First-Party Data Important
  • Example of First-Party Data
  • How to Collect First-Party Data
  • How to Use First-Party Data
• First-Party vs Third-Party Cookies
• Data Privacy and Compliance
  • How to Manage the Consent and Privacy for First-Party Data
  • Why Consent Management & Data Privacy Matter for First-Party Data
• How UniConsent Helps Publishers Collect Consented First-Party Data
• About UniConsent

First-Party vs Third-Party Data Comparison

For publishers, first-party data is the asset to build on: it comes from readers who already trust you, it can be packaged into audience segments for advertisers, and you control how consent is collected and respected.

What Is First-Party Data?

First-party data is information that is collected about a user via a company where a user is directly an audience or a customer. The company owns the digital marketing data sources such as websites, mobile apps, CRM, social media etc.

First-party data is used to identify consumer preferences, including:

• Demography: age, gender, income, education, geographic location
• Interests, hobbies and passions
• Purchase history and intentions
• Visit and interactions logs
• Etc

First-party data is considered more valuable because of the quality of the data, the trust and relationship you have built with the user.

First-party data collected with consent can also be segmented and monetised like third-party data by using a first-party data management platform like PubSurge.

Why Is First-Party Data Important

Data is important for a business to make better decisions, better marketing, utilise personalised ads and services to increase the chance of a conversion.

There are reasons why first-party data is more important in the future:

• Data privacy legislation and technology are making data sharing and selling more difficult, so first-party data is more important.
• Browsers restrict third-party cookies: Safari blocks them and Firefox isolates them by default, and Chrome blocks them in Incognito mode and lets users block them in settings. Third-party scripts can track fewer users across the internet.
• First-party data gives more control: easy to collect, easy to erase, easy to keep updated and in control of the user, allowing a company to use data based on consent that can change from time to time.

Example of First-Party Data

First-party data is essentially data that is generated when a user interacts with the assets of your business.

Examples of first-party data:

• Data collected in your CRM
• Data and cookies collected in your website
• Data collected with first-party data DMP
• Completed surveys
• Customer feedback
• Support tickets
• Emails collected with newsletters
• Social profile of users
• Subscription-based emails
• Products the user looked at
• Articles the user interacted with
• Time spent on websites

How to Collect First-Party Data

The normal ways of collecting first-party data include Google Analytics, mobile apps, social media, customer surveys, support tickets and messages, customer service emails, SMS, CRM and point of purchase interactions. You can also collect additional data such as user interactions, gather and manage all first-party data with a Data Management Platform (DMP) like PubSurge.

How to Use First-Party Data

• Identifying consumer preferences
• First-party data programmatic advertising
• Gain audience insights
• Predict future patterns and user interactions
• Personalise content and advertisements

Compare with Zero-Party Data, Second-Party Data, Third-Party Data

While first-party data is the data that you own, second-party and third-party data is what you can buy from another company or exchange value with another company to benefit both parties through user collected data.

Second-party and third-party data is data from users that you don’t have a direct relationship with. So the trust and data quality is lower.

Zero-party data is a subset of first-party data that users volunteer on purpose, such as preferences or survey answers. See the comparison table above for a side-by-side view.

First-Party vs Third-Party Cookies

A first-party cookie is set by the website the user is visiting, the domain shown in the address bar. Publishers use first-party cookies for logins, preferences, analytics and their own audience data. A third-party cookie is set by another domain whose script, pixel or iframe loads on the page, such as an ad tech vendor, and can recognise the same user across different websites.

• Safari blocks third-party cookies by default (since 2020).
• Firefox keeps each site's cookies in a separate jar with Total Cookie Protection, on by default since 2022.
• Chrome still allows third-party cookies by default and blocks them in Incognito mode. In April 2025 Google decided not to launch a standalone choice prompt, and in October 2025 it announced the retirement of most Privacy Sandbox APIs, such as Topics and Protected Audience.

Under the GDPR and the ePrivacy rules, non-essential cookies need consent before they are set, whether they are first-party or third-party. Learn more in All About Cookies and see how to block third-party cookies in each browser.

Data Privacy and Compliance

CCPA and GDPR have redefined how a company can receive, store, and distribute customer data. The general rules are keeping the process of using first-party data transparent, collecting consent for first-party data and allowing users to update the data and opt out if they want.

How to Manage the Consent and Privacy for First-Party Data

Firstly, you have to provide a solid privacy policy to users and keep the process transparent about how you will use a user's first-party data.

Secondly, you must collect explicit consent from users for first-party data with a CMP like UniConsent.

Thirdly, provide preference management features to allow users to update and change the data and consent they have given, making it an on-going relationship between the company and the user.

Why Consent Management & Data Privacy Matter for First-Party Data

Due to privacy laws such as GDPR, CCPA companies need to take the audience’s consent before collecting personal data and respect their choices or allow users to opt out through a clear and easy to understand way.

Under the GDPR, every use of first-party data needs a lawful basis under Article 6, such as consent, contract or legitimate interests, and personalised advertising normally relies on consent. On top of that, the EU ePrivacy rules require consent before storing or reading non-essential cookies and similar identifiers on a user's device. This applies to first-party cookies for analytics and personalisation just as much as to third-party cookies.

Consent Signals for Advertising: Google Consent Mode and IAB TCF

Collecting consent is only half of the job: the choice has to reach every tag and ad partner that uses your first-party data.

• Google Consent Mode v2 passes the user's choices (ad_storage, analytics_storage, ad_user_data and ad_personalization) to Google tags. Google requires it for users in the EEA and UK to keep using personalisation and measurement features in Google Ads and Google Analytics.
• IAB TCF records the user's choices for each purpose and vendor in a TC String that SSPs, DSPs and Google Ad Manager read before they use data for advertising. Google requires publishers serving ads with AdSense, Ad Manager or AdMob in the EEA, UK and Switzerland to use a Google-certified CMP integrated with the TCF.
• IAB GPP and Global Privacy Control carry US opt-outs of sale and sharing to your ad partners.

For a broader look at how privacy regulations have reshaped digital marketing strategy, including consent rate optimisation, compliant audience building, and first-party data collection at scale, see our guide to privacy marketing.

How UniConsent Helps Publishers Collect Consented First-Party Data

UniConsent for publishers is a Google-certified, IAB TCF registered CMP that puts your first-party data on a clear legal footing:

• Consent before collection: non-essential first-party and third-party cookies and tags are blocked until the user agrees, then loaded for each purpose the user accepted.
• First-party CMP domain: serve the CMP from your own subdomain with a first-party CMP domain, so consent scripts load as first-party requests.
• IAB TCF: TCF v2 consent strings and Google Additional Consent for your SSPs, DSPs and Google Ad Manager.
• Google Consent Mode v2: built-in Consent Mode support for Google Ads, Google Analytics and Ad Manager.
• US privacy: IAB GPP and Global Privacy Control for opt-outs of sale and sharing.
• Preference centre and proof of consent: users can change or withdraw consent at any time, and each choice is logged.

About UniConsent

UniConsent consent management platform is a part of Transfon User Experience Platform serve tens of millions of users per day for global marketers and publishers to provide a seamless user experience. Contact us to know more: hello@uniconsent.com