O2 Slovakia, s.r.o. is a provider of mobile service in Slovakia. O2 started as Telefónica in Slovakia with commercial services on 2 February 2007 with about 600.000 preregistered users, and ~400,000 Slovaks actively using the O<sub>2</sub> service. The operator has 2 370 000 active users today. The company is subsidiary of O2 Czech Republic, itself owned by PPF.
Users are identified by prefix 940, 944, 948 and 949 in mobile number. (+421 94x yyy yyy)
O2 Slovakia, s.r.o, Pribinova 40, 811 09 Bratislava, Slovakia