Third-party tracking is becoming less effective with each browser update and privacy regulation change. Organizations that continue relying on it face degrading data quality and compliance risks.
Third-party tracking refers to the practice where a tracker on a website is set by a different website than the one the visitor is currently viewing. Third-party trackers are code snippets typically installed across multiple websites. They collect and send information about a user’s browsing history to other companies, usually for advertising purposes. When the same tracker appears on many sites, it can build increasingly complete user profiles over time.
Why effectiveness is declining
Ad blockers and browser restrictions like Safari’s intelligent tracking prevention (ITP) or Firefox’s enhanced tracking prevention (ETP) make third-party tracking less effective with each update. Safari blocks third-party cookies by default. Firefox does the same. Chrome has delayed third-party cookie deprecation multiple times, but the direction is clear.
The practical impact: if you’re measuring campaign performance or user behavior using third-party cookies, you’re working with incomplete data. You’re missing Safari users entirely, Firefox users, and anyone using ad blockers. For some organizations, that represents 40–50% of their traffic.
Compliance considerations
Beyond technical limitations, companies face legal exposure using third-party cookies without complying with privacy laws. The Privacy and Electronic Communications Regulations (PECR) in the UK and the German Telecommunications and Telemedia Data Protection Act (TTDSG) specifically address third-party tracking and require explicit consent before setting these cookies. Getting that consent becomes difficult when users increasingly understand that third-party cookies enable cross-site tracking.
Migration path
If you’re still using third-party cookies, audit which third-party scripts you’re running. Many marketing teams discover they’re loading trackers they no longer even use.
Migrate to first-party data collection where possible. This means implementing server-side tracking, using first-party cookies properly, and building direct relationships with your customers. Understand the difference between what you can track now versus what you’ll be able to track in twelve months, and plan accordingly.
Learn more about ITP from our blog post: What Intelligent Tracking Prevention (ITP) means for web analytics & marketing [Updated]
Find more details about third-party tracking on the Piwik PRO blog:
- “Cookieless future” is just a buzzword – Here is all you need to know about the end of third-party cookies
- Third-Party Data: How Does it Fit into Today’s Marketing Landscape?
To learn about differences between various types of customer data, read our articles:
