Fixing cross-domain and iframe booking tracking in GA4 for Devonshire Hotels

01// The broken state

Devonshire Hotels and Restaurants runs five properties (the Devonshire Arms at Bolton Abbey, Devonshire Fell, the Cavendish Hotel, the Devonshire Arms at Beeley, and the Pilsley Inn) across several websites, each with its own booking journeys for hotels, boltholes, spa, dining, and weddings. GA4 was not capturing bookings reliably: the Residiary restaurant widget loaded inside an iframe, a stray space made the hotel name inconsistent across events, cross-domain complexity broke source and campaign attribution, bolthole bookings on the Anytime Bookings domain pushed no dataLayer events, Google Ads and Facebook conversion tracking was broken, and the session timeout and 2-month data-retention windows were too short. A booking-engine migration also meant the tagging had to be rebuilt.

02// What we changed

1. aFixed the Residiary restaurant booking widget so bookings inside the iframe are tracked, via postMessage
2. bRemoved the stray space so the hotel name is consistent across every event
3. cRebuilt cross-domain attribution and the bolthole dataLayer events on the Anytime Bookings domain
4. dExcluded payment-gateway referrals and corrected the session-timeout and data-retention windows
5. eAdded item-level custom dimensions (nights, dates, guest count, hotel name) and CTA tracking
6. fRestored Google Ads and Facebook conversion tracking for the new booking engine, excluding non-revenue restaurant bookings
7. gBuilt Looker Studio dashboards by booking category and by website, including sold-out-item insight

03// The outcome

Across a two-phase build we fixed the iframe restaurant tracking, removed the duplicate hotel-name events, and rebuilt cross-domain attribution so nearly all conversions tie back to source, medium, and campaign, leaving only a 2-3% residual gap from ad blockers and older browsers. Booking tracking is now reliable across all five properties and every category (hotels, boltholes, spa, dining, weddings), Google Ads and Facebook conversion tracking is restored for the new booking engine, and Looker Studio dashboards report item-level ecommerce by category and website, including popular sold-out items.