The retail media landscape is undergoing a seismic shift. As retailers look to expand their reach and revenue beyond their owned properties, offsite retail media is emerging as a powerful force. Offsite retail media ad spend is expected to grow at twice the rate of on-site spend through 2026, according to eMarketer. In fact, U.S. offsite retail media ad spending is predicted to rise by 42.1% in 2025, more than double the growth rate of on-site ad spend (15.3%).