Except for a few lines (e.g. #41), trams are still slow. Buses and trolleybuses come and go pretty often but are also very crowded. It is recommendable to watch out your stuff on buses and other means of public transportation. All city buses, trolleys and trams, as well as preorășenesc buses (buses going to villages and towns in the vicinity of Bucharest) are owned and run by the RATB, Bucharest’s public transportation company. All of them work only with RATB plastic cards (bought and chargeable at RATB kiosks located at main stops, open 06:00 AM - 08:00 PM; one can add credit also online at https://online.ratb.ro/, in Romanian only) which need be validated (i.e. pressed against the orange machines found onboard) upon boarding the vehicle. Do that and wait for the green light to flash or, if the red one flashes, it means either you’ve run out of credit or it did not work, so that you need add some credit or do that again. Bus / tram / trolleybus drivers are not entitled to sell cards and disregarding of the reason for your not validating your card (running out of credit, forgetting, the bus is too crowded etc.), you will be fined if an inspector finds you without a valid / validated card. Passes also exist and they are a good idea if you plan on using public transport twice a day or so. A one month pass valid on all RATB vehicles (except express lines) costs RON 50. Subway passes can also be charged on the RATB card, but only at a RATB kiosk, not in a subway station ticket office. In such a case, when entering the subway station, use the orange machines (similar to those on a bus) instead of the green ones.
Express buses (such as bus # 783 running between Bucharest OTP Airport and the southern section of Unirea Square or the 780 linking the airport with the main railway station) work with these cards or with special 2 or 10 rides magnetic cards looking similarly with the metro ones; if using them, they must be validated too when boarding the bus, through the green machines to the right of the driver. For RATB fares, check out http://www.ratb.ro (they are currently RON 1.30 / ride within the city except for the 780/783 buses). When taking into consideration surface public transport, also notice that traffic can make a 2 km. ride take half an hour or even more. When and if possible, take the subway during the rush hour, even if you have to walk for a while afterwards. It helps your physical condition anyway.
There are more and more private companies running minivans coming and going everywhere but they are generally more expensive and crowded, with routes changing every now and then; particularly not recommended if you have large bags and such, as they have no luggage space and the aisle is very narrow. Taxis are not expensive (about RON 1.39-1.80 / km.), provided you look around for one belonging to reputable companies such as Cobălcescu, Cocoșatu’, Rodell, Leone (tel.: 9425), Meridian (tel.: 9444, 9888), CrisTaxi (tel.: 9461,9466), Getax (tel.: 9530). For more info on taxis, refer to my special post here.