Third-party cookies are dying. 5 concrete strategies to prepare your marketing — first-party data, server-side tracking, Consent Mode v2, and more.
The third party is leaving. What it means for your marketing
Google Chrome, the browser with a 65% market share, is gradually blocking third-party cookies. Safari and Firefox have been blocking them for years. For marketers, this means one thing — traditional methods of ad targeting, retargeting, and conversion measurement are breaking down.
If your campaigns depend on third-party cookies for remarketing, lookalike audiences, or cross-domain tracking, you need to act. Not next year — now.
What exactly stops working
Third-party cookies enabled three key things:
- Retargeting — showing ads to people who visited your site (via third parties)
- Cross-site tracking — tracking users across websites for better targeting
- Attribution — assigning conversions to specific channels or campaigns
First-party cookies (your own) stay. GA4 still works. But remarketing through display networks and similar platforms will be significantly limited.
Warning: If your marketing strategy relies primarily on third-party remarketing and lookalike audiences, you’ll lose 40–60% of reach. Unprepared advertisers will see rising CPA and falling ROAS.
5 strategies that work without third-party cookies
1. First-party data as the foundation
Collect your own data directly from customers. Emails, phone numbers, purchase history, website behavior — all of this belongs to you and no browser change can take it away.
In practice:
- Solid CRM (HubSpot, Salesforce, or even a simple system)
- Newsletter with real value (not spam)
- Loyalty programs and member sections
- Forms with clear value exchange (checklist, e-book, calculator)
Tip: Customer Match in Google Ads and Custom Audiences in Meta Ads run on first-party data. Upload your email list and target existing customers or their lookalikes — without a single third-party cookie.
2. Server-side tracking
Traditional tracking (JavaScript tags in the browser) is increasingly blocked — ad blockers, ITP in Safari, cookie restrictions. Server-side tracking moves data collection to your server, where the browser has nothing to block.
Google Tag Manager Server-Side Container allows you to:
- Send data from your server directly to Google Ads, GA4, Meta CAPI
- Maintain conversion measurement accuracy
- Control what data you send (GDPR compliance)
- Bypass ad blockers (data goes through your domain)
Implementation requires technical expertise and a server (Google Cloud Run, Stape.io), but the investment pays off in more accurate data and better campaign optimization.
3. Google Consent Mode v2
Since March 2024, Consent Mode v2 is mandatory for advertisers in the EEA. Without it, Google Ads and GA4 lose data on users who declined cookies.
Consent Mode v2 uses conversion modeling — Google estimates the behavior of users who didn’t consent based on patterns from those who did. Result: up to 70% more accurate data compared to no Consent Mode.
Two modes:
- Basic — sends no data without consent (minimum for compliance)
- Advanced — sends anonymized pings even without consent, enables modeling (recommended)
4. Contextual targeting instead of behavioral
Before the cookie era, advertising worked on context — running shoe ads on sports websites. This approach is coming back, in a better form thanks to AI.
Google Ads offers contextual targeting via topics and keywords in display campaigns. Meta uses Advantage+ targeting, which targets based on content and signals without cookies.
Important: Contextual targeting doesn’t depend on any cookies, is fully GDPR compliant, and users perceive it as less invasive than behavioral tracking.
5. Enhanced Conversions and Privacy Sandbox
Enhanced Conversions in Google Ads sends hashed first-party data (email, phone) along with the conversion. Google matches them with its sign-in data, giving you more accurate attribution — without third-party cookies.
Privacy Sandbox with Topics API in Chrome assigns interest categories to users anonymously. As an advertiser, you don’t need to implement anything — Google Ads integrates it automatically.
From practice: For an e-commerce client, we switched from third-party cookie remarketing to Customer Match + server-side tracking + Consent Mode v2. Result: CPA dropped 18% and measured conversions increased 35%.
Checklist: preparing for the cookieless future
- Audit current tracking — identify where you depend on third-party cookies
- Implement Consent Mode v2 (Advanced) — mandatory minimum
- Set up server-side tracking — at least for Google Ads and Meta CAPI
- Build first-party data — CRM, newsletter, loyalty programs
- Switch to Customer Match and Enhanced Conversions
- Test contextual targeting in display and video campaigns
Need help transitioning to cookieless marketing?
At ADS Agency, we implement server-side tracking, Consent Mode v2, and first-party data strategies. We’ll prepare your marketing for a world without cookies.
- Third-party cookies are ending — Chrome is blocking them, Safari and Firefox already have
- First-party data (emails, CRM) is the foundation of new marketing — no browser change can take it away
- Server-side tracking preserves measurement accuracy even when cookies are blocked
- Consent Mode v2 (Advanced) is mandatory for EEA advertisers since March 2024
- Contextual targeting is back — thanks to AI, it’s more accurate than ever
