First-Party and Third-Party Cookies in Digital Marketing Explained

Cookies are a key part of digital marketing, powering everything from personalized website experiences to targeted advertising. First-party cookies are created by the websites you visit, while third-party cookies track you across sites.

As third-party cookies are phased out, marketers must adapt their strategies. This post explains the differences between these cookies, their role in marketing, and what the future holds for data-driven campaigns.

What Are Cookies?

Cookies are small data files that websites store on your device to save information like login details, preferences, or activity. They’re designed to make your browsing experience smoother by remembering things for you.

For marketers, cookies are valuable tools for tracking user behavior and delivering personalized content or ads. However, the way cookies are used—and how much control users have over them—varies depending on whether they’re first-party or third-party cookies.

Let’s take a closer look at what sets these two types apart.

What Are First-Party Cookies?

First-party cookies are created and stored by the website you’re visiting directly. They remember useful information like your login credentials, language preferences, and items in your shopping cart.

For businesses, first-party cookies are essential for creating personalized experiences and gathering analytics to improve their websites. Because these cookies are only accessible by the website that sets them, they are considered more privacy-friendly compared to third-party cookies.

What Are Third-Party Cookies?

Third-party cookies are created by domains other than the website you’re visiting. These cookies are often placed by advertisers or analytics platforms and track your activity across multiple websites.

Their primary purpose is to build detailed user profiles for targeted advertising and retargeting. While useful for marketers, third-party cookies have raised significant privacy concerns, leading to tighter regulations and efforts by browsers to phase them out.

Key Differences Between First-Party and Third-Party Cookies

First-party and third-party cookies serve distinct purposes in how websites collect and use data. First-party cookies focus on improving user experience on a single website, while third-party cookies track users across multiple sites for advertising and analytics.

Here’s how they differ:

Who Sets Them

First-party cookies are created and stored directly by the website you’re visiting. They work exclusively on that domain, saving data like your preferences, login details, or items in your cart. 

On the other hand, third-party cookies are set by external domains, such as ad networks or analytics services. These cookies are embedded in the site you’re visiting but are managed by third-party entities with their own interests, typically advertising or tracking.

Access

A first-party cookie is only accessible to the website that created it. This limited scope ensures that any data collected remains tied to that specific domain.

In contrast, third-party cookies can track users across multiple sites, creating a more detailed profile of browsing habits. This access is what makes third-party cookies a powerful tool for advertisers but also a source of significant privacy concerns.

Privacy Implications

First-party cookies are considered more privacy-friendly because they focus on enhancing your experience within a single website. They don’t collect data beyond what’s necessary for personalization or analytics on that site. 

Third-party cookies, however, have sparked widespread criticism for their role in invasive tracking practices. They collect data across multiple sites without users always being fully aware, fueling debates around transparency and consent.

Examples in Practice

When you log in to a website and it remembers your credentials on your next visit, that’s a first-party cookie at work. Similarly, if an e-commerce site saves items in your cart even after you navigate away, it’s using first-party cookies. 

In contrast, third-party cookies power the ads that seem to follow you around the web, promoting products you looked at on entirely different sites.

First-party cookies provide essential tools for personalization and analytics, making them a cornerstone of effective, privacy-conscious marketing. Third-party cookies, while useful for broader ad targeting, are being phased out due to growing privacy concerns.

This shift challenges marketers to rethink strategies, focusing on building direct relationships with users through first-party data and exploring new technologies like server-side tracking or contextual advertising. Adapting now ensures long-term relevance and compliance in a changing digital landscape.