The city had granted a concession to the two private street companies until 1924, after which the city could expropriate the companies. Both companies where well run and highly profitable, and on 1 May 1924 KSS and KES were merged and taken over by the city council, giving the new company the name A/S Kristiania Sporveier. On 1 January 1925 the city changed its name to Oslo, with the company's name also changing. The suburban tramways operated by Holmenkolbanen and Ekebergbanen were not taken over, as was the Lilleaker Line operated by KES; the city council did not want to take over tram lines in the neighboring municipality of Aker.