If my customers want hotels in small towns and not just the big cities, will a hotel booking API actually have them?

Usually yes, but not always, and it depends on the supplier behind the API rather than on the portal itself. Most hotel suppliers hold very wide inventory that goes well beyond capital cities and tourist resorts, so searches for regional towns, business districts and smaller holiday spots normally return something. Where coverage thins out is in genuinely remote places, in small family run guest houses, and in homestays or serviced apartments that have never signed up with any wholesaler. If a property is not contracted anywhere upstream, no API can invent it for you.

The practical fix is to not rely on a single source. When your portal is connected to more than one hotel supplier, the gaps rarely line up, so a town that is thin with one supplier is often well covered by another, and your customers see a fuller list without knowing anything changed. Beyond that, you can load your own directly contracted properties into the portal so the small hotels you personally deal with sit in the results alongside supplier inventory. That is how most agencies cover their home region properly, because they know those hotels better than any wholesaler does.

How many suppliers you can connect, and which ones are available to you, depends on your plan and on your own contracting status with those suppliers, so it is worth asking before you commit to a particular setup. Some suppliers also restrict certain markets or require you to sell only in agreed countries.

Before you go live, make a short list of the towns your customers ask for most often and run live test searches on each one, then tell us where the results look thin so we can look at which supplier mix would fill those gaps.