Safari already limits your JavaScript cookies to 7 days—and just 24 hours if the URL contains tracking parameters like fbclid or gclid. While everyone panics about Chrome’s third-party cookie deprecation, WordPress store owners are losing attribution data to Safari ITP right now. The 2.9x revenue uplift from first-party data strategies isn’t theoretical. It’s the gap between stores that adapted and stores still fighting yesterday’s battle.

The Real Cookie Crisis Isn’t What You Think#

Here’s what most “cookie deprecation” articles get wrong: they focus entirely on Chrome killing third-party cookies while ignoring Safari’s first-party restrictions that affect 24% of your traffic today.

Two different problems need two different solutions:

• Third-party cookie deprecation (Chrome): External domains can’t track you across sites. Facebook’s pixel can’t follow users from site to site. This affects cross-site tracking.
• First-party cookie restrictions (Safari ITP): YOUR cookies on YOUR domain are limited to 7 days when set via JavaScript. This affects your own attribution windows.

Chrome allows first-party cookies up to 400 days. Safari caps them at 7 days (or 24 hours with tracking parameters). Firefox has its own restrictions. The fragmentation is the problem.

You may be interested in: Server-Side Tracking for WordPress in 2026: The Complete Beginners Guide Without GTM

What First-Party Data Actually Means#

First-party data is information collected directly from your customers, on your domain, with their knowledge. It’s the data that survives every privacy restriction because it’s fundamentally ethical.

First-party data includes:

• Purchase history and order data
• Account information and preferences
• Email newsletter signups
• On-site behavior (pages viewed, products browsed)
• Customer support interactions
• Form submissions and lead data

Third-party data includes:

• Cross-site tracking cookies from ad networks
• Purchased audience segments from data brokers
• Inferred demographics from external sources

The distinction matters: 71% of consumers buy more from brands that are transparent about their data practices. First-party data collected with consent isn’t just compliant—it builds trust.

The Cookie Restrictions Actually Affecting WordPress Stores#

Let’s get specific about what’s happening to your tracking:

Safari ITP (Affecting 24% of Traffic)

JavaScript-set cookies expire after 7 days. If the URL contains tracking parameters (gclid, fbclid, utm_source), that drops to 24 hours. Your Google Ads attribution window just shrank from 90 days to one day for Safari users.

Server-set cookies (via HTTP headers) can bypass this limit if they’re set from your own domain with matching IP.

Chrome (Affecting 65% of Traffic)

Third-party cookies are being phased out, but first-party cookies remain unaffected with up to 400-day lifespans. Chrome users aren’t your immediate problem—Safari users are.

Firefox ETP (Affecting 3-5% of Traffic)

Enhanced Tracking Protection blocks third-party cookies by default and restricts some first-party tracking. Similar pattern to Safari.

The cumulative impact: without adaptation, you’re making decisions based on incomplete data from a significant portion of your visitors.

You may be interested in: CAPI and Enhanced Conversions Don’t Need Cookies

Server-Set Cookies: The Safari Workaround#

Safari ITP restricts JavaScript-set cookies. But cookies set via HTTP response headers from your own server don’t face the same limits—as long as the IP address matches.

This is where first-party server-side tracking becomes essential.

When events route through your own subdomain (like data.yourstore.com), cookies can be set server-side with full lifespans. The browser sees them as legitimate first-party cookies from your domain, not JavaScript tracking scripts.

Transmute Engine™ is a first-party Node.js server that runs on your subdomain. The inPIPE WordPress plugin captures events and sends them via API to your Transmute Engine server, which can set proper first-party cookies and route data to GA4, Facebook CAPI, and other platforms—all from your own domain.

What this solves:

• Safari ITP bypass: Server-set cookies from your domain aren’t restricted to 7 days
• Ad blocker bypass: Requests go to your subdomain, not blocked third-party domains
• Attribution recovery: Longer cookie windows mean accurate attribution for more visitors
• Data ownership: Events pass through your infrastructure first

The First-Party Data Strategy That Works#

75% of marketing leaders are investing more in first-party data strategies specifically because of cookie deprecation. Here’s what that actually looks like for WordPress:

1. Collect Data Server-Side

Client-side JavaScript tracking is unreliable. Move to server-side collection that captures events on your server before browser restrictions interfere. This is the foundation.

2. Use Your Own Domain

First-party means YOUR domain. Events tracked via your subdomain (data.yourstore.com) are treated as legitimate first-party requests. Third-party domains get blocked.

3. Route to APIs, Not Pixels

Facebook CAPI, Google Ads Enhanced Conversions, and GA4 Measurement Protocol don’t need cookies. They accept server-side event data directly. This eliminates cookie dependency entirely for platform reporting.

4. Store Raw Data in BigQuery

Your own data warehouse means you’re not dependent on any platform’s data retention or processing. BigQuery gives you raw event data for analysis, AI training, and compliance—forever.

5. Get Consent and Be Transparent

First-party data collected with proper consent is the ethical high ground. €5.88 billion in cumulative GDPR fines by January 2025 shows the cost of getting this wrong. But consent-based first-party data? That’s exactly what regulators want.

Key Takeaways#

• Safari already restricts first-party cookies to 7 days (24 hours with tracking parameters)—this isn’t future, it’s now
• Chrome allows 400-day first-party cookies—the problem is Safari, not Chrome
• Server-set cookies bypass Safari ITP when served from your own domain
• First-party data delivers 2.9x revenue uplift versus third-party strategies
• 75% of marketing leaders are already investing in first-party data strategies
• APIs like Facebook CAPI don’t need cookies at all—server-side tracking eliminates the dependency

The cookie survival strategy isn’t complicated: collect first-party data, on your domain, server-side, with consent. Get started at seresa.io.