Lake Ontario Becomes “Lake America”

WASHINGTON — President Donald Trump has formally ordered the U.S. government to rename Lake Ontario “Lake America,” turning an escalating dispute with Canada into an extraordinary battle over one of North America’s most familiar geographic names.

Trump signed an executive order Thursday, August 27, directing the Department of the Interior and the U.S. Board on Geographic Names to make “Lake America” the official designation used by the federal government.

The order requires the Geographic Names Information System to be updated within 30 days. Federal agencies will then use “Lake America” on government maps, documents and official communications.

There is an important limitation, however: the United States cannot force Canada to change the name.

Lake Ontario is shared by the United States and Canada, with New York along its southern and eastern shores and the Canadian province of Ontario covering much of its northern and western shoreline. Canada controls roughly 52 percent of the lake's surface area and is under no obligation to recognize Washington's new terminology.

Canadian maps can continue to say “Lake Ontario,” as can international organizations, private publishers and map services that choose not to follow the U.S. government's designation.

Trump had previewed the move earlier in the week on Truth Social, posting a map on which “Lake Ontario” was crossed out and replaced with “Lake America.” He linked his proposal to deteriorating U.S.-Canadian trade relations and suggested that the United States expected to conduct significantly less business with Ontario.

Ontario Premier Doug Ford responded dismissively, saying Trump could call the lake whatever he wanted — even “Lake Trump” — but that Canadians would continue calling it Lake Ontario.

The dispute comes as relations between the longtime allies have deteriorated sharply over tariffs and trade. Washington has imposed steep new duties on Canadian products, while Canada has announced retaliatory tariffs on hundreds of U.S. goods.

Lake Ontario covers approximately 7,340 square miles and is the smallest of the five Great Lakes by surface area. Toronto, Canada's largest city, sits along the northwestern shore. The lake is also a vital part of the Great Lakes-St. Lawrence transportation system connecting the continent's industrial heartland with the Atlantic Ocean.

The move follows Trump's January 2025 executive order changing the federal U.S. designation of the Gulf of Mexico to the “Gulf of America.” Mexico did not adopt that name.

Trump has also repeatedly spoken about Canada becoming America's 51st state and has continued to express interest in acquiring Greenland, comments that have generated strong reactions abroad.

For the U.S. federal government, Lake Ontario will now officially become Lake America.

For Canada, it remains Lake Ontario — and Washington has no authority to change that.