Third-party cookies have played a major role in how online advertising and tracking work – but they’re also at the center of some of the biggest changes happening on the web today.
In this article, we’ll break down what third-party cookies are, how they work, and why they’ve been so important for marketers. You’ll learn how to enable or block them, check whether a website uses them, and understand their role in affiliate marketing. We’ll also look at how they differ from first-party cookies, what’s changing as browsers like Chrome phase them out, and how this all ties into compliance.
| ⚠️UPDATE: Google announced that it will no longer pursue its plans to phase out third-party cookies. Instead, the company will introduce a new solution: a one-time prompt that allows users to set their preferences, which will apply across all Google browsing experiences. |
If you’re looking for clear, practical answers about third-party cookies, you’re in the right place.
| Third-party cookies are small text files created by websites other than the one a user is currently visiting. These files are stored on the user's device and can be accessed by the third-party website to track user activity across different sites. |
In other words, they are data files that a browser stores on a user’s device, created by a domain different from the one the user is visiting. These cookies are most commonly introduced via embedded content, such as advertisements, analytics scripts, or social media widgets, hosted on the third-party’s servers and integrated into the primary website’s code.
Third-party cookies example: you visit a website to check out a pair of glasses, and a third-party cookie from an ad network like Facebook is placed in your browser. Later, while browsing other sites, you see ads for those same glasses or similar styles because the cookie tracks your visit.
Their technical function enables third-party domains to track a user’s behavior across multiple websites over time, forming the foundation of cross-site tracking.
| The primary purpose of third-party cookies is to gather information about users' online activities |
Cookies collect data such as browsing patterns, preferences, and sometimes personal details. Advertisers and marketing companies use this information to build comprehensive user profiles, which they use for targeted advertising. These cookies allow advertisers to deliver personalized ads across various websites, improving the efficiency and impact of online marketing efforts.
In affiliate marketing, cookies are crucial in determining which ads should be served to the right audience at the right place and time.
Here is an overview of what benefits third-party cookies offer to digital marketing:
With increasing restrictions on third-party cookies, their impact on digital marketing is clear. Marketers must find alternatives and adjust to these changes to keep their strategies effective.
| The extinction of Google Chrome third-party cookies is a significant challenge for the digital marketing world. If Chrome eventually disables third-party cookies, marketers and advertisers will lose a critical tool for tracking user behavior across sites, delivering personalized ads, and accurately attributing conversions. |
For many, this change would disrupt long-established marketing strategies.
Let’s get through the steps of third-party cookie operation.
Step 1. Initial request
When a user loads a webpage with third-party content (for example, from an external ad network), the user’s browser sends a request to the third-party server to retrieve that content.
Step 2. Cookie creation
Next, the third-party server sends back a cookie that includes data like a unique user ID, timestamps, and other tracking information.
Step 3. Cross-site tracking
When a user visits other websites with cookies from the same third party, the server can access them in their browser. This allows the server to recognize users and track their activity across websites. As a result, a detailed profile of a user’s browsing habits is created.
Step 4. Ad serving
Based on the created user profile, advertisers serve targeted ads that align with the user’s preferences and past online behavior. It increases the chances of user conversion.
3rd-party cookies are created by domains other than the one you are currently visiting. When you visit a website, that site may include content from external sources, such as ads, embedded videos, or analytics tools. These external sources can place cookies on your browser, even though you’re not directly interacting with them.
For example:
These cookies can track your online activity across multiple websites, enabling targeted advertising, cross-site analytics, and personalization.
If you need to add third-party cookies to your website, here is how to do it.
Understand the legal grounds
Third-party cookies fall under regulations like GDPR, CCPA, and other global or regional privacy laws. Before implementing them on your website, it’s essential to understand and comply with the relevant legal requirements. Even if your region has no specific restrictions, your users may come from areas with stricter rules.
These regulations are designed to increase transparency and protect user privacy by preventing unethical or unregulated tracking. Websites that don’t clearly disclose what data is collected or how it’s used can face penalties. This includes information such as cookies and IP addresses, which can identify users even when they browse anonymously.
Set a cookie consent banner
Before collecting users’ information using cookies, you must obtain their consent. To do so, you need to implement a cookie banner. Our blog has an all-in-one cookie banner guide, so we won’t discuss it now. Instead, we recommend you refer to the guide for details.
Set the goals of third-party cookies
What are third-party cookies going to help you accomplish? In other words, think through the collected data applications. It can include:
Integrate third-party cookies (consent mode)
The next step is to add the necessary scripts to your website's HTML to set the cookies.
You have to do it in the <head> or <body>.
Test your implementation
Check if cookies are being set using your browser's developer tools. In Chrome DevTools, follow these steps:
Ctrl+Shift+I / Cmd+Option+I).Monitor performance
Keep an eye on your website’s performance and verify that cookies are functioning as intended. Use tools like GTM, GA4 DebugView, or third-party testing services to monitor and test cookie behavior effectively.
You can check whether a website uses third-party cookies in several ways.
Browser settings
Most browsers have a privacy or security section in their settings where you can view cookies stored by websites. Look for entries under domains other than the main website's domain.
Browser Extensions
Some browser extensions can tell you whether a website uses cookies or other scripts. For example, uBlock, primarily an ad blocker, also provides information on scripts and cookies used on websites. Such extensions are easy to install and provide quick insights into a site's cookie usage.
Chrome DevTools
A more tech way to check for cookies would be to use Chrome DevTools.
Ctrl+Shift+I (Windows/Linux) or Cmd+Option+I (Mac).Blocking third-party cookies is one of the easiest and most effective ways to prevent cross-site tracking, limit personalized ads, and reduce the amount of data shared with advertisers. Most modern browsers like Chrome, Safari, and Firefox now offer built-in settings to block these cookies and enable strict tracking protection.
To block third-party cookies, follow these steps based on the browser you are using:
For Google Chrome:
1. Go to Settings. Go to Privacy and Security.
2. Choose Cookies and other site data.
3. Select Block third-party cookies.
For Mozilla Firefox:
1. Open Settings. Go to Privacy & Security.
2. Under Enhanced Tracking Protection, choose Strict or customize to block third-party cookies.
For Microsoft Edge:
1. Go to Settings. Move to Privacy, search, and services.
2. Under Tracking Prevention, select Strict.
For Safari (macOS/iOS):
1. Open Preferences. Go to Privacy.
2. Enable Prevent cross-site tracking.
For Opera:
1. Go to Settings. Go to Privacy & security. Go to Cookies and site data.
2. Enable Block third-party cookies.
Blocking third-party cookies improves privacy. This is true. However, it may negatively affect the user's website performance.
In short, while Google third-party cookies are still around, the industry is still moving toward better privacy and new ways of targeting and measuring ads replying to zero-party and first-party data. Our blog also provides more information on zero-party vs first-party data on our blog.
| Related: Data trends in digital marketing |
Third-party cookies have been the biggest tool for tracking user behavior for years, but with privacy regulations tightening worldwide, they’ve become a bit of a headache. Plus, more and more browsers (like Chrome, Safari, and Firefox) are blocking them, which makes things even trickier for businesses.
Server-side tracking is the solution, and Stape makes it easy to set up. It lets you use first-party cookies to control your data and simplify privacy compliance. It can be configured for various platforms, including server-side Google Analytics, Google Ads, Meta, and many other platforms.
With server-side tracking, you can still collect essential data for your marketing but in a way that respects users' privacy and preferences. Thus, it’s a win-win: effective tracking without the constant cookie drama.
Let us give you an example of how server-side tracking with Stape can help your business.
We have power-ups that make cookies last longer.
Keeps cookies safe on the server, so they don’t get deleted or blocked by browsers. Stape offers standard cookies for Pro plan users and as for Business-tier users and above, you can also use any additional custom cookies.
Custom Loader makes Google Tag Manager and Google Analytics scripts harder to block by ad blockers and ITP. It changes how gtag.js and gtm.js are loaded. It also works with Custom Domain to set first-party cookies and extend their lifetime.
Let’s compare first-party cookies and third-party cookies.
| Criteria | First-party cookies | Third-party cookies |
| Purpose | Track users on a specific website. | Track users across multiple sites, which helps with targeted advertising and customer insights. |
| Privacy concerns | Low. Only track users within a single site. | High, often blocked or restricted due to privacy issues. |
| Compliance | Easier to manage for compliance. | Restricted by data policies and data restriction laws increasingly. |
| Reliability | Stable and reliable data collection. | Getting less reliable due to browser blocking and limitations. |
| Data control | Full control over data within the website. | Limited control over user data, as it's shared across different sites. |
| Personalization | Strong | Strong but website-specific |
| Future | Stable | Uncertain |
For businesses in 2025, relying on first-party cookies is a safer choice. While we cannot tell you to throw Chrome 3rd party cookies out of the picture, it’s wise to have options other than relying solely on them. First-party cookies offer better privacy protection, make it easier to comply with data laws, and create a smoother user experience. While third-party cookies offer some benefits for targeted advertising, they also present increasing challenges and risks. Focusing on first-party data and using privacy-first tracking methods will help you stay ahead in a more privacy-conscious digital world.
We answered the most common questions on third-party cookies you might have in 2025.
Third-party cookies remain crucial to marketing strategies. They fuel insights and personalization. However, as privacy regulations multiply and become tougher, and browser restrictions and tracking prevention tools become more substantial, the future of third-party cookies isn’t guaranteed. To get the most out of cookies while you still can is a good strategy, but finding alternatives that can withstand the demands of a privacy-centered world is essential as well.
Stape has lots of options! Click on Try for free to register and check all the benefits.
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