Your hotel,
double-checked.

Lesser-known booking sites buy hotel rooms through different wholesale channels and spend less on advertising, so their listed rates are sometimes lower. Often not for a room it names, though, which is exactly why Underbook tells you whether the cheaper listing names the same room.

We compare the room names the booking sites publish. When the cheaper site names a room that matches, we mark it “same room name”: strong evidence, not proof. When it names no room or a different one, we say so plainly, so you can check the room and cancellation terms before you book. We never assume.

Google does list some of these sites, but they're buried below the sponsored results most people click. Underbook checks them for the exact stay you're looking at and brings the result to you.

If you book through a site we surface, we may earn a small commission from that site. You pay nothing extra. We'll show you the lower rate even when our commission would be smaller — the comparison is for you, not us.

When you open a hotel page, Underbook sends the hotel name, your dates and your party size to its price service to look up current rates. Nothing that identifies you goes with it. We never see or store your payment details, booking happens on the site you choose, and we don't sell your data.

Yes. Underbook is a free extension on the Chrome Web Store. Add it and it checks the next hotel page you open.