Route number is 21A. Remember it—the number stays the same everywhere: on the stop display, in apps, on the vehicle itself. Look for 21A specifically. If you're not sure you found the right stop, just ask someone nearby: 'Does bus 21A stop here?'

This route serves the Budapest (Hungary) region. In larger metro areas, routes can pass through several districts or towns. To know for sure if it works for you, pull up the route map and check the key stops and direction.

Operator is BKK. This is the official company responsible for the route. If you run into problems (rude driver, breakdown, dirty vehicle, delays)—contact them. It helps to note the time, direction, and route number—makes your complaint more specific and gets handled faster. Contact info is usually on the company website or in transit apps.