Google Analytics 4 Replaces Universal Analytics

What Changed

In March 2022, Google announced that Universal Analytics, the long-standing version of Google Analytics, would stop processing new data on July 1, 2023, with an extra year for paying Analytics 360 customers. Google described it as built for desktop browsing, separate sessions and cookies. Its replacement, Google Analytics 4 (GA4), works across websites and apps, doesn't rely only on cookies, uses an event-based data model, and doesn't store IP addresses.¹

A year later, from the week of July 1, 2024, Google removed access to all Universal Analytics data, current and historical, in the interface and through the API. Its goals and ecommerce transactions stopped feeding linked Google Ads accounts, which could affect Smart Bidding, and its audience lists closed.²

A Different Set of Numbers

GA4 isn't Universal Analytics with a new interface. Everything is an event, including page views, and events no longer have Universal Analytics' category, action and label structure.³ Familiar metrics changed meaning: "Users" in GA4 reports means active users rather than total users. Google says differences of up to 10% in page views and up to 20% in users and sessions between the two are to be expected for the same traffic.⁴

GA4 also holds less detail for less time. In standard properties, user-level and event-level data is kept for 2 or 14 months before it's deleted automatically.⁵ And reports that include demographics or similar signals can be thresholded: rows are withheld when there aren't enough users to prevent anyone identifying individuals.⁶

Why It Mattered

Unlike most changes on this timeline, this one came from a product update rather than a privacy rule, and it changed a tool many marketers report from every day. Year-over-year comparisons broke at the switch, history from before the migration was lost unless it had been exported, and teams had to set up conversions and audiences again.

It also tied analytics more closely to the privacy changes around it. Google announced that GA4 wouldn't store IP addresses a month after European regulators found standard Google Analytics setups unlawful, as the EU-US data transfer article describes, and GA4 works with Consent Mode, which models conversions for visitors who decline cookies. Modelled and withheld data became a normal part of analytics reports.