Stratford Municipal Airport, is located 2NM northeast of the city of Stratford, Ontario, Canada. Its location identifier designation was changed from CNM4 to CYSA effective 20 September 2012.The airport is classified as an airport of entry by Nav Canada and is staffed by the Canada Border Services Agency (CBSA). CBSA officers at this airport can handle general aviation aircraft only, with no more than 15 passengers.