Can I search for a room for a family with children through a hotel booking API and get the right price for the kids?

Yes, you can, as long as you send the number of children and the age of each child with the search. Hotel booking APIs treat children differently from adults, and almost every supplier decides the price from the age, not just from the head count. If you send only the number of guests without ages, you will usually either get an error back or a price that is worked out as if everyone in the room were an adult, which is normally higher than what the family should pay.

The reason the ages matter so much is that each hotel sets its own rules. One property may let a young child stay free in the existing beds, another may charge for an extra bed, and another may treat an older child as an adult from a certain birthday onwards. When you pass the ages, the supplier applies the correct rule for that property and the price you show your customer is the price the room really costs.

There are limits worth knowing about. Every hotel has a maximum number of people allowed in one room, so a larger family may need two rooms rather than one, and the search will simply return nothing if you ask for more guests than a room can hold. Some suppliers also collect a charge for a child at the hotel instead of in the booking, and whether that shows in your results depends on the supplier and on what your plan gives you access to.

Before you go live with family searches, run a test booking with children of different ages on your own portal and compare what comes back with what the hotel itself is showing, so you know the ages are reaching the supplier correctly.