Google to use UK and EU user IP addresses for ad personalization

Starting August 3, 2026, Google will begin utilizing the IP addresses of users across the United Kingdom, the European Economic Area (EEA), and Switzerland for the purposes of advertisement measurement and personalization. This pivot constitutes a notable departure from the company’s previous public stances regarding digital identifiers. While Google has long utilized location data to serve localized content, the explicit integration of IP addresses into its core ad-targeting engine for European users represents a calculated risk in a region governed by the world’s strictest data protection mandates.

This development arrives against a backdrop of nearly a decade of tension between Silicon Valley’s data-driven business models and European regulators. Previously, Google characterized the use of granular signals like IP addresses as a circumvention of user privacy—an "opaque" practice that the company claimed to be moving away from in favor of more anonymous, cohort-based tracking methods. The industry at large has been grappling with the "Privacy Sandbox" initiative, which sought to deprecate third-party cookies. However, as the timeline for cookie deprecation has repeatedly slipped, Google appears to be recalibrating its toolkit to maintain ad efficacy without violating the letter of the law.

The mechanics of this change involve leveraging the IP address—a unique string identifying a device on a network—to infer highly specific geographical data and cross-device patterns. Under the new policy, these addresses will act as a stabilizing signal for advertisers who have struggled with the signal loss caused by App Tracking Transparency (ATT) on iOS and the general decline of traditional tracking cookies. By formalizing the use of IP addresses for "measurement and personalization," Google is effectively creating a middle ground: it provides advertisers with the precision they demand while attempting to wrap the process in a framework that ostensibly complies with the GDPR’s "legitimate interest" or consent-based requirements.

The timing of this pivot is particularly sensitive due to the ongoing deliberations by the UK’s Information Commissioner’s Office (ICO) and the European Data Protection Board (EDPB). Regulators are currently scrutinizing the "pay or consent" models and the transparency of algorithmic profiling. By announcing this change nearly two years in advance, Google is likely attempting to preemptively bake these practices into the "new normal" of the digital economy, daring regulators to challenge a practice that is already standard for many smaller ad-tech players but carries immense weight when deployed at Google’s scale.

From a market perspective, this move suggests that the dream of a truly "cookieless" and signal-free web is being replaced by a more pragmatic, albeit more invasive, reality. For years, Google championed a narrative of "privacy-first" advertising. This latest policy shift indicates that the technical challenges of replacing cookies with purely anonymous signals were perhaps too great to sustain the growth rates required by shareholders. By returning to IP addresses, Google is reinforcing its dominant position, as its vast ecosystem of logged-in users allows it to verify IP-based inferences in a way that independent ad-tech companies cannot match.

Looking ahead, the primary focus will be on the response from European privacy advocates and the specific implementation of consent mechanisms. If the ICO or EEA regulators determine that an IP address is "personal data" that requires explicit opt-in for personalization—rather than just for security or basic delivery—Google could face a wave of litigation similar to those involving the "Right to be Forgotten." Furthermore, the industry will watch closely to see if other tech giants like Meta or Amazon follow suit, potentially leading to a standardized European advertising tier where the IP address serves as the primary, if controversial, anchor for digital marketing.