Western New York (WNY) is the westernmost region of the U.S. state of New York. The eastern boundary of the region is not consistently defined by state agencies or those who call themselves "Western New Yorkers". Almost all sources agree WNY includes the cities of Buffalo, Niagara Falls, Jamestown, and the surrounding suburbs, as well as the outlying rural areas of Niagara Frontier, and Chautauqua-Alleghany (or the western Southern Tier). Many would also place Rochester and the Genesee Valley in the region, although these locations are also sometimes included in the Finger Lakes Region.
The State of New York sometimes defines the WNY region as including just five counties: Allegany, Cattaraugus, Chautauqua, Erie, and Niagara. The state's Empire State Development Corporation and state health authorities have both mapped the region this way. The state has also used this regional boundary to set policy during the COVID-19 pandemic.