The advertising industry has been discussing the death of third-party cookies for years. While Google reversed its plan to remove cookies from Chrome in 2024, third-party cookie blocking is already the default in Safari (which has blocked them since 2017) and Firefox. The direction of travel is clear: tracking that relies on third-party cookies will continue to degrade, and advertisers who build robust first-party data infrastructure now are better positioned for whatever regulatory or browser changes come next.
What Third-Party Cookies Are and Why They Are Going Away
A first-party cookie is set by the domain you are visiting (your Shopify store sets cookies on its own domain). A third-party cookie is set by a different domain — like Meta or Google — via a script that loads on your website. These cookies allow Meta and Google to track users across many different websites, building profiles of browsing behaviour that inform ad targeting and attribution.
Third-party cookies are going away because of privacy concerns. They enable extensive cross-site tracking without users’ explicit consent, which is incompatible with GDPR, the California Consumer Privacy Act, and a growing number of privacy regulations worldwide. Browser makers — particularly Apple with Safari — have implemented Intelligent Tracking Prevention that blocks or severely limits third-party cookies.
What Cookieless Tracking Means for Your Shopify Ad Campaigns
Attribution gaps are already here
If you are running Meta Ads and a significant portion of your customers use iPhones with Safari, you already have attribution gaps. Safari’s ITP limits cookie lifespans, meaning Meta cannot reliably track users who click an ad on one day and purchase several days later. Meta’s native attribution window of 7 days becomes unreliable for Safari users after about 1 day.
Audience targeting becomes less precise
Interest-based targeting and behavioural targeting on ad platforms rely on third-party data about user behaviour across the web. As third-party cookies decline, the data underpinning these audiences degrades. Broad targeting audiences become less effective; first-party audiences (your own customer lists, website visitors) become relatively more valuable.
Retargeting is the most affected
Cross-site retargeting (showing ads to users who visited your website while they browse other sites) depends heavily on third-party cookies. Without them, platforms cannot identify that a user who visited your Shopify store and a user browsing another site are the same person. Retargeting campaign performance will degrade as cookie availability decreases further.
What to Do Now: Building a Cookieless Tracking Foundation
1. Implement server-side event tracking
Server-side tracking (Meta CAPI, Google Measurement Protocol, TikTok Events API) sends conversion events from your server using first-party customer data (hashed email, hashed phone) rather than browser cookies. This is completely immune to cookie restrictions and ad blockers. Purchase attribution quality improves because the match is based on real customer identifiers, not ephemeral cookies.
2. Build first-party audiences
Customer list audiences (uploaded from your Shopify customer export) are based on email addresses, not cookies. They work regardless of cookie availability. Build and maintain:
- All-time customer list (all Shopify buyers)
- High-value customer list (top 20% by LTV)
- Recent purchasers (last 90 days)
- Email subscribers who have not purchased
3. Use first-party cookies where possible
Server-side GTM with a custom subdomain (gtm.yourdomain.com) sets first-party cookies on your domain instead of third-party cookies from google-analytics.com. First-party cookies are not blocked by ITP in the same way and have longer lifespans, improving attribution for Safari and Firefox users.
4. Expand email and SMS capture
Email and SMS are first-party channels where you communicate directly with customers without depending on cookies or ad platform tracking. Growing your subscriber list now gives you cookieless-proof direct marketing capability for the future.
What Is Already in Place That Helps
Several tools in the current ad ecosystem are designed for the cookieless direction:
- Meta’s Advantage+ audiences: uses Meta’s own first-party data (users’ Facebook and Instagram activity) rather than cross-site third-party cookies
- Google’s Privacy Sandbox: Topics API and Protected Audience API are Google’s proposed replacements for third-party cookie-based advertising; currently in testing
- Google Enhanced Conversions: first-party hashed data matching for conversion attribution without cookie dependency
The Practical Priority for Shopify Store Owners
The most impactful single action: implement Meta Conversions API with hashed first-party customer data. This is the biggest lever for maintaining Meta attribution quality as cookies decline, and it is available now regardless of the browser privacy direction.
Book your free Shopify tracking audit here and we will assess how exposed your current tracking setup is to cookieless degradation and what to prioritise to protect your attribution quality.