In the past, most marketers relied on the now‑infamous third‑party cookies that tracked visitors across sites to personalise offers and attribute campaigns. But with major browsers now deprecating these third-party methods, attention is shifting toward first‑party data and cookieless approaches.
With privacy-centric methods like server‑side tagging and consent-based event measurement, marketing teams can still capture the contextual and behavioural signals they need to connect with target audiences and personalise content.
This guide explores first-party cookies and their use in marketing. We’ll discuss their benefits, how they differ from third-party cookies and their value in web analytics workflows, especially in marketing attribution. Finally, we’ll highlight potential risks to keep in mind and best practices to implement first-party cookies while promoting data minimisation, transparency and trust.
What are first-party cookies?
First-party cookies are a type of tracking code that helps a site remember visitor preferences. They keep people signed in, preserve baskets between pages, recall language and region choices and connect page views so analytics data can count user sessions and attribute conversions.
They also give marketing teams direct customer behaviour signals without third-party intermediaries, which improves reporting accuracy and aligns with GDPR and other privacy requirements.
Unlike Google Analytics and most legacy solutions that were initially designed around cross-site tracking, privacy-first tools are built around direct user interactions. These ethical analytics platforms focus on extracting insights while still respecting user privacy.
How do first-party cookies work?
When someone visits your website, your domain creates a small text file (the “cookie”) through your site’s script or web server and stores it in their browser to remember them.
Then on future visits or pageviews, the browser returns the same value to your domain, allowing you to link actions throughout a user session or over a short time frame.
First-party vs third-party
First-party cookies are set and read by the site a person visits. Third-party cookies originate from embedded domains and are used for advertising purposes. Here’s a breakdown of their characteristics:
First-party cookies | Third-party cookies | |
Purpose | User experience & convenience | Gather user data |
Who creates them | The website itself | Advertisers and other third parties |
What they track | User preferences, login state, language, shopping cart contents | User behaviour, social media activity, browsing history |
Browser support | Widely supported | Blocked by default or being phased out on many popular browsers. |
While first-party cookies raise fewer ethical and privacy concerns, they still handle personal data and must be managed carefully. If responsibly implemented, with a clear purpose and transparency, they can provide significant benefits.
Benefits of first-party cookies
First-party cookies provide marketing teams with the necessary signals while keeping data within the bounds a visitor has chosen. The result is better measurement, clearer choices and a stronger foundation for privacy.
Clear ownership
Unlike tracking cookies used by advertisers and other third parties, first-party cookies are created and set by the website owner. Since tracking stays on your site and is limited to the purposes you declare, it’s much easier to explain to users. Visitors know exactly who is collecting their data and why, which builds trust.
Consistent data quality
Because first-party cookies travel between a browser and the site a person is on, they work consistently across your own pages.
Teams get steadier session counts, cleaner attribution within a domain and fewer gaps caused by blocked third-party requests.
You can also define sensible expiries to keep user data fresh, which improves the quality of conversion and cohort analysis.
Transparency and control
First-party setups are easier to explain and manage. You can show plain-language descriptions and provide a preference centre that lets people opt in or out later.
It is straightforward to rotate identifiers, shorten lifetimes and minimise what you store. Clear naming and documentation create an audit trail that your legal and security teams can review.
Compliance support
Regulators emphasise transparency, purpose limitation and choice. Under the GDPR, CCPA and similar frameworks, data shouldn’t be kept any longer than necessary for the purpose it was collected. What’s considered a “reasonable” cookie expiry period varies by jurisdiction and industry.
First-party setups can be configured to support GDPR and similar rules by defining specific purposes, collecting only the minimum data, honouring consent, and setting sensible expiries.
Teams should:
- Document expiry decisions and align them with local regulator guidance.
- Review expiries regularly as part of compliance checklists and audits.
- Adjust retention periods when business needs or regulatory expectations change.
Data privacy considerations with first-party cookies
First-party strategies avoid the broad cross-site profiling that made third-party cookies contentious. But they still involve personal data, so they require careful handling and safeguarding. Reusing identifiers or failing to obtain consent can increase data privacy risks.
Consent management issues
Under GDPR and similar laws, non-essential cookies need a lawful basis. So analytics and personalisation require consent. As an organisation using first-party cookies, make sure to stick to the following best practices:
- Describe purposes in plain language.
- Honour preferences on every page load.
- Ensure settings sync across subdomains.
- Use a consent management platform.
Data storage and security considerations
Limit what a cookie stores. Keep values short, avoid storing sensitive data in the browser and set sensible expiration times.
Secure attributes such as HttpOnly and SameSite help reduce exposure. In your systems, restrict access, log reads and changes and retain data only as long as needed for the declared purpose.
Cross-device tracking limitations
First-party cookies are browser-bound. They don’t link phones, tablets and laptops without an account or server-side logic. You can either accept these limits or consider explicit, consent-based methods such as signed-in measurement.
Balancing personalisation with privacy
Considering data privacy when using first-party cookies also means: Start with data minimisation. Use the least intrusive signal that achieves the goal. Prefer session-level metrics when possible.
And always keep in mind to provide value in return for consent and make controls easy to find. The aim is to create more positive user experiences that respect data subjects’ choices and privacy.
Potential for misuse despite being “first-party”
Without proper implementation, first-party strategies can still have privacy risks. Watch out for common pitfalls to avoid. These include:
- Overly long lifetimes: Don’t keep identifiers longer than necessary, it can feel invasive and increase risk. Many tools default to 30‑day lifetimes, but privacy‑focused teams usually adopt shorter, purpose‑bound limits in the 7 to 14 day range.
- Fingerprint‑like IDs: Avoid using highly specific or persistent identifiers that resemble device fingerprinting
- Undisclosed reuse or repurposing: Be transparent if you reuse cookie data across contexts or for new purposes.
- Sensitive data combinations: Be cautious when combining cookie data with sensitive information or using it for profiling or targeting.
- Rights handling: Users have the right to access or delete, or object to how their data is used. Make sure these options are easy for them to find and act on.
To avoid these pitfalls and make sure your first-party strategy is effective, start with the best practices below.
First-party cookie implementation best practices
Done well, first-party cookies can support useful analytics and respectful personalisation. Follow the steps below to maintain a clear, auditable and user-centric setup.
Consent mechanisms
To meet the GDPR’s lawful basis, make sure to implement user-friendly consent mechanisms. Keep in mind to:
- Group cookies by purpose.
- Make it easy to change or withdraw consent.
- Obtain consent before setting non-essential cookies.
Value exchange
Help visitors understand how their choices shape their experience. You can add explanatory text to your cookie banners, for example:
- “Analytics cookies help us improve site performance and page loading times.”
- “Session cookies keep you signed in and save the items in your shopping cart.”
- “Preference cookies load the site with your preferred language and display settings.”
- “Personalisation cookies tailor content and product recommendations to your interests and region.”
Data minimisation
To minimise privacy risk and support compliance, make data minimisation a top priority. Its core principles include the following:
- Store only what is necessary.
- Default to short randomised user IDs.
- Align expiries with purpose.
- Use session cookies where possible.
- Scope strictly necessary cookies to the smallest path or subdomain that still works.
Audits & cookie lifecycle management
To encourage accountability and avoid unchecked cookie growth, conduct regular cookie audits and follow the following approaches:
- Maintain a cookie inventory that includes the name, purpose, domain, expiry date and owner.
- Regularly review inventory and remove legacy entries.
- Apply Secure, HttpOnly and SameSite attributes to strengthen browser protection.
- Enforce data retention limits
- Rotate identifiers regularly.
Privacy by design principles
To align internal privacy controls with regulator expectations, its crucial to understand privacy as a core principle of ethical marketing and embed it deep into your analytics approach:
- Conduct DPIAs for new feature releases or data uses.
- Opt for privacy-enhancing technology.
- Implement role-based access controls.
- Log all reads and changes, and document decisions for review and future reference.
When implemented with these safeguards, first‑party cookies can support ethical analytics and improve customer relationships.
From tracking to trust
First‑party cookies foster more respectful and transparent relationships with customers. When aligned with jurisdictional requirements and industry best practices, they’re effective and ethical analytics tools.
If your team needs a privacy-first approach to analytics, consider Matomo. It’s an open-source platform that lets you easily configure privacy settings to align with GDPR, CCPA and other privacy laws.
Whether you choose on-premises deployment or Matomo Cloud, you have full control over your customer data and everything you need to interpret user behaviour while still respecting their privacy.
Download Matomo On-Premise completely free, or start a 21-day free trial of Matomo Cloud.
