Ottawa Macdonald–Cartier International Airport (IATA: YOW, ICAO: CYOW) is the primary international airport serving Ottawa, the capital of Canada, and the surrounding National Capital Region. The airport is located in the south end of the city, approximately 10.2 kilometres south of downtown Ottawa, and covers 1,700 hectares of land.
The airport is named after Sir John A. Macdonald, Canada’s first Prime Minister, and Sir George-Étienne Cartier, a Father of Confederation. It is operated by the Ottawa International Airport Authority, which manages the airport under a lease from Transport Canada.
YOW serves as a focus city for Air Canada and Porter Airlines, and is the second-largest base for Porter Airlines after Toronto Billy Bishop. The airport offers flights to destinations across Canada, the United States, and several international destinations, connecting Ottawa to more than 40 non-stop destinations.
In 2025, Ottawa Macdonald–Cartier International Airport served approximately 5.2 million passengers, a 4% increase over 2024. The airport is also an important hub for general aviation, cargo, and government and military flights, given Ottawa’s status as the national capital.
The airport features three runways: Runway 07/25 (2,438 m), Runway 14/32 (3,048 m), and Runway 04/22 (1,006 m). The main terminal building houses both domestic and international operations, with US preclearance facilities for flights to the United States.