Budapest's network of public transport services includes buses, trolleybuses, trams, underground trains (Metró) and over ground suburban trains (HÉV). Buses, trams and trolleybuses run daily from 4.30 a.m. until 11.0 p.m. All three Underground lines connect at Deák tér Station, and service frequencies range from 15 minutes late in the evening to every two minutes at peak times. The HÉV runs to and from Csepel Island and Ráckeve in the south, Szentendre in the north, and Gödöllő in the east.

Tickets have to be bought before boarding; you cannot usually buy them from the driver and there are no conductors. They are available at Underground stations, tobacconists and newsagents, and from vending machines at many bus and tram stops in the city centre. They are valid for one single journey of any length (without changing) on all routes (including the Cogwheel Railway, but excluding those parts of the HÉV that lie outside the metropolitan boundary of Budapest). Special tickets can be purchased that allow a change of route, and that cover the HÉV outside Budapest. There is also a range of pre-paid books of tickets and value-for-money passes (e.g. 1-day and 3-day).

A new ticket has to be validated at the beginning of each journey, and this is done by inserting it into the slot in the small red box situated at waist height near the doors of buses, trolleybuses, trams and HÉV trains. Please note on the Underground system these boxes are in the stations and the escalator. There are lots of ticket inspectors: some are uniformed and others plain-clothed, but they always wear a red armband and carry a photographic identification badge. They can ask to see tickets and passes on any vehicle and anywhere on the Underground system, including after you have got off - so please remember to validate your ticket and keep hold of it!