Who benefits from Google’s SERP? The impact of the DMA on the Air Travel Market

Abstract

This paper examines the impact of Google’s Search Engine Results Page (SERP) redesign, implemented on March 6, 2024, to comply with the Digital Markets Act (DMA), on web traffic to airline and flight comparison websites. The reform removed the Google Flights module and introduced new sections — “Airlines Options” and “Flight Sites”—to improve visibility for third-party services. Using a Difference-in-Differences (DiD) approach and Similarweb traffic data for six EU countries and the United Kingdom as a control group, we estimate the causal effects of the SERP changes between July 2023 and December 2024. Results reveal significant increases in organic traffic to airline websites, especially for low-cost carriers (LCCs), smaller national operators, and airlines with limited visibility. Organic traffic to LCCs rose by 15% on desktop and 8.5% on mobile devices. In contrast, network carriers and dominant national airlines experienced negligible effects. For comparison sites, gains were concentrated on lesser-known platforms (up to 12.7%), while prominent platforms like Skyscanner and Booking.com did not benefit from increased organic traffic but may have gained indirectly through referral traffic. Overall, the redesign seems to have redistributive effects, enhancing visibility for smaller actors and increasing competition in the digital air travel market.