How much would renaming Lake Ontario cost the U.S.? CBO points to the ‘closest precedent’

A Canadian flag flies along the waterfront of Lake Ontario, in Toronto, Ontario, Canada, on August 27, 2026. Photo by COLE BURSTON /AFP via Getty Images

Article content

Renaming Lake Ontario to “Lake America” will come at a cost to federal agencies in the U.S. that are responsible for updating maps and databases, and a previous report by the Congressional Budget Office (CBO) offers insight into how expensive this could be.

Article content

Article content

Article content

Article content

It’s not the first time Trump has sought to rename a major body of water. In January 2025, he signed an executive order changing the name of the Gulf of Mexico to the “Gulf of America.”

Article content

Article content

Following this, in April 2025, CBO published a report estimating that the Gulf of Mexico name change could cost up to US$500,000 between 2025 and 2030.

Article content

In an email to National Post, a spokesperson for CBO said: “CBO hasn’t published an estimate for H.R. 10196, the Lake America Act. The closest precedent is the estimate for H.R. 276, the Gulf of America Act. While that estimate can’t automatically be applied to Lake Ontario, it can provide a sense of how CBO has previously treated similar legislation.”

Article content

The  2025 report said the estimate was based on the cost of similar activities that involved updating documents and maps. It added that the Gulf of America Act “could affect direct spending by some agencies that are allowed to use fees, receipts from the sale of goods, and other collections to cover operating costs.”

Article content

U.S. President Donald Trump shows off his proclamation marking Feb. 9 as Gulf of America Day while flying above the basin aboard Air Force One. Photo by ROBERTO SCHMIDT /AFP via Getty Images

Article content

However, CBO estimated that any changes in spending by those agencies would be negligible because “most of them can adjust amounts collected to reflect changes in operating costs.”

Article content

Article content

If the cost of renaming Lake Ontario does come in at a similar figure to the estimate for the Gulf of Mexico, it would mean U.S. federal agencies may have spent as much as US$1 million on renaming the two bodies of water.

Article content

Article content

Elsewhere, the CBO issued another report earlier this year estimating the cost of introducing “Department of War” as a secondary title for the U.S. Department of Defense, after Trump signed an executive order authorizing the use of the new name in September 2025.

Article content

It said a “modest implementation” of the name could cost US$10 million, or as much as US$125 million if the name change was implemented “broadly and rapidly.” A statutory renaming, the CBO said, could cost hundreds of millions of dollars.

Article content

Article content

Another post that showed a map of New Mexico with “Mexico” crossed out and replaced by “America” was reminiscent of posts he made before renaming Lake Ontario.

Article content