Google Analytics 4 (GA4) is Google's current analytics platform for measuring website and app traffic, user behaviour, and conversions. It replaced Universal Analytics (UA) in July 2023, when Google stopped processing new UA data. GA4 uses an event-based data model — every user interaction (page view, scroll, click, purchase) is captured as an event — compared to UA's session-based model. GA4 also includes built-in privacy controls, machine learning-powered insights, and cross-platform tracking across websites and mobile apps in a single property.
GA4 is free and provides every UK business with access to detailed analytics data about how visitors find and use their website. Despite its importance, many UK businesses still have GA4 incorrectly configured — with missing conversion events, unconfigured filters that include internal traffic, and no connected Google Search Console data. A properly configured GA4 installation provides the data foundation for every other digital marketing decision.
Key GA4 reports and what they tell you
- Acquisition reports — where your traffic comes from (organic search, paid ads, social media, direct, email, referral); essential for understanding which marketing channels work
- Engagement reports — which pages visitors view, how long they stay, and what content generates the most engagement
- Conversion reports — how many users complete key goals (form submissions, purchases, phone clicks, sign-ups); requires conversion events to be configured first
- Retention reports — how many users return to your website over time; particularly important for content and email marketing effectiveness
- User demographics — age, gender, location, device type, and interests of your audience; useful for persona validation
- Funnel exploration — custom analysis of multi-step conversion processes to identify where users drop off between steps
GA4 setup essentials for UK businesses
- Add the GA4 tracking code to every page of your website (via Google Tag Manager is recommended)
- Configure conversion events for your key business goals (form submissions, phone clicks, purchases, newsletter sign-ups)
- Connect Google Search Console to GA4 for organic search query data
- Set up IP filtering to exclude your own team's internal traffic from reports
- Enable Google Signals for enhanced demographic reporting (requires user consent under UK GDPR)
- Set the data retention period to 14 months (the maximum) to preserve historical comparison data
GA4 has more privacy features than Universal Analytics — including IP anonymisation by default, server-side data processing options, and data deletion tools — but it is not automatically GDPR compliant simply by using it. UK GDPR requires informed consent before setting non-essential cookies (including GA4's measurement cookies). Your website must have a compliant cookie consent mechanism that gives users genuine choice, and GA4 should not collect personal data (names, emails) through custom events. Many UK businesses configure GA4 in Consent Mode v2 to respect user consent choices while maintaining some analytical capability for non-consenting users through modelled data.
Google ended Universal Analytics data processing on 1 July 2023. UA properties stopped collecting new data and, subsequently, access to historical UA data was removed. Businesses that have not migrated to GA4 have lost their historical analytics data. GA4 cannot import historical Universal Analytics data, so any business that did not export their UA data before access was revoked has permanently lost that historical information. GA4 has been the only active Google Analytics product since mid-2023.