Lake Ontario Has a New Name? Here’s What Happened

Written by: Keya Gambhir

Imagine opening a map and seeing that a lake you have known by the same name for years suddenly has a different name. That is what happened this week with Lake Ontario, one of the five Great Lakes of North America.

On August 27, 2026, U.S. President Donald Trump signed an executive order directing the U.S. government to use the name “Lake America” for Lake Ontario. The order applies to how the U.S. federal government refers to the lake. However, it does not require Canada, other countries, international organizations, or other groups to use the new name.

So, is Lake Ontario actually called Lake America now?

The answer depends on who you ask.

A Lake Shared by Two Countries

Lake Ontario is part of the Great Lakes, which sit along the border between the United States and Canada. About 52% of the lake’s surface area is in Canada, while the rest is in the U.S. state of New York.

Because the lake is shared by two countries, changing its name is more complicated than simply changing a label on a map. The U.S. government can decide what name it uses in its own official records, but it cannot force another country to use that name.

Canadian officials have said they will continue to call the lake Lake Ontario. The name has been used for more than 400 years, dating back to before Canada and the United States became the countries they are today.

Why Did the Name Change?

The name change happened during a period of disagreements between the United States and Canada over trade.

Trade is the buying and selling of goods between countries. The U.S. and Canada have large amounts of trade with each other. Recently, the two countries have disagreed over tariffs and other trade issues. A tariff is a tax placed on goods brought into a country.

Trade negotiations between the two countries broke down shortly before the lake’s name was changed. The name change therefore became part of a larger period of disagreement between the neighboring countries.

Who Decides What Places Are Called?

You might think there is one worldwide organization that decides the official name of every lake, river, mountain, and ocean. But there isn't.

Different countries and organizations can have their own systems for geographic names. In the United States, the federal government maintains an official database called the Geographic Names Information System. The executive order directed the U.S. Department of the Interior to update the U.S. government's records for the lake.

This means you could see different names depending on where you are or which organization produced a map.

This Has Happened Before

Lake Ontario is not the first major body of water whose name has been changed by the U.S. government.

In 2025, President Trump ordered the U.S. government to use the name “Gulf of America” instead of “Gulf of Mexico.” Different countries and organizations responded differently to that change. For example, maps can display different names depending on the user's location.

For Lake Ontario, the situation is similar: the U.S. federal government is using the new name, while Canada continues to use the older name.

What Happens Next?

For now, the lake itself has not moved or changed. Its water, location, wildlife, and size are all the same. What has changed is the name the U.S. federal government has directed its agencies to use.

The situation also shows why geographic names can be more important than they might seem. Names can connect places to history, languages, cultures, and the people who have lived around them for generations.

For anyone looking at a map, the most important thing to know is simple: Lake Ontario and “Lake America” refer to the same Great Lake. The difference is which name a particular government, organization, or country chooses to use.