The majority of helicopters cannot fly above 8,000 ft. The SA .315 Lama, however, set a record by flying at 41,000 feet. It regularly operates at over 20,000 feet. It is the world's highest-flying helicopter. In India, it is called the Chetak.
The test pilot Jean Boulet flew the MI-12 Lamma to a height of 40,000 feet and on that same flight, he also grabbed the record of the longest autorotation over a helicopter, as the engine failed as soon as he lowered the power due to extreme cold and lack of air into the engine. Most helicopters, however, are not very well suited to high altitude flight. By their nature, helicopters are not suited for high altitudes.