Book early for
- Big events (festivals, trade fairs, sports finals), when cities sell out and prices spike.
- Peak season at beach and ski destinations.
- Small towns with few hotels.
Last-minute can work for
- Big cities with lots of hotel supply, outside events and holidays.
- Business-heavy cities on weekends, when corporate demand drops.
Best of both
Lock in a free-cancellation rate early, then re-check closer to the date and rebook if it drops. Compare across booking sites and the hotel's own site, and include taxes and fees.