Propeller aircraft and commercial jets fly in what layer of the atmosphere?

Propeller aircraft and commercial jets typically fly in the lower to middle portions of the atmosphere, primarily within the troposphere and the lower stratosphere. Commercial jets usually cruise at altitudes between 30,000 and 40,000 feet, which places them in the lower stratosphere. Propeller aircraft often operate at lower altitudes, usually within the troposphere, depending on their design and purpose.