After World War II, Bulgaria was ruled by a communist government and Dzhambov's workshop was nationalised.

In 1962, the company started production of the models M65 and M66 on Škoda 706 RTO chassis, which became very common on city and intercity services.

Although the vehicles closely resembled their German counterparts, they were developed to fit the Škoda 706 RTO chassis, which produced buses without an analogue among Setra's model line.

Similar to the Setra S150, Chavdar developed the intercity model 11M4, which had a Hungarian Rába D2156HM6U engine and won several prizes from international fairs.

In the end of the 1970s the midi bus Chavdar 5C was constructed by Kiril Hadjiev and Lubomir Toshev and the first prototypes were tested in 1979.

Despite rivalry from major Western European manufacturers, Chavdar won the tender and delivered 200 solo buses to Athens.

In 1984, Chavdar signed a contract with the Austrian Steyr-Daimler-Puch to produce city and suburban buses under license with production starting in 1988.

Due to financial instability and the difficult economic situation in the country following the fall of the communist regime, Chavdar declared bankruptcy in 1999.

Chavdar exported its production to the USSR, Czechoslovakia, Greece, North Korea, Afghanistan and Nicaragua among others.