Underbook

Underbook is a free extension for Chrome, Edge and Firefox (Android too). On a hotel page at Booking.com, Expedia and other booking sites, it shows if another site lists the stay for less (all-in where taxes and fees are reported), if that price names the same room and if free cancellation is labelled. Free price-drop emails, even after you book. No account. If you book through it, we may earn an affiliate commission at no extra cost to you. It never changes which rates we show or their order.