Which Lakes Rank as the Largest in the United States?

The U.S. is renowned for its breathtaking lakes, from the expansive Great Lakes to the stunning alpine beauty of Lake Tahoe, known for its transparent waters. The country is richly endowed with numerous impressive water bodies.

Although many of these lakes are undeniably vast, their exact rankings may not be common knowledge, leading to the question: Which lakes are the largest in the U.S.?

To address this question, we’ll explore a variety of lakes, ranging from freshwater bodies to highly saline ones like the Salton Sea and the Great Salt Lake. Additionally, we’ll examine the distinctions between man-made reservoirs and naturally occurring lakes.

Measuring the Largest Lakes

To simplify our analysis, we’ll focus on the largest lakes based on their surface area.

Lakes vary greatly in depth, with some being extremely deep and others quite shallow. This naturally influences the volume of water they contain. For instance, a smaller lake with significant depth might be considered "larger" in terms of water volume compared to a wide but shallow lake.

As a result, our evaluation will center solely on surface area. This approach aligns with the common perception of "biggest," which typically conjures images of expansive lakes, irrespective of their depth. (For those interested in the deepest lake in the U.S., we’ve addressed that topic elsewhere.)

Additionally, the category is inclusive: We’ll examine both naturally formed lakes and artificial reservoirs, as well as freshwater and saline lakes.

5 Largest Lakes in the U.S.: All Great Lakes

Unsurprisingly, the Great Lakes dominate as the largest lakes in the country. These five interconnected lakes are situated along the U.S.-Canada border.

These lakes are also ecologically vital, supporting diverse plant, bird, mammal, and fish species, while supplying water resources for both wildlife and human populations in the region.

While none of these lakes lie entirely within U.S. borders, they aren’t entirely outside either. With acknowledgment of our shared stewardship (and freshwater resources) with Canada, we proudly rank them at the top of our list.

1. Lake Superior (31,700 sq mi / 82,000 sq km)

True to its name, Lake Superior stands as the largest among the Great Lakes and holds the title of the biggest lake in the United States.

Bordered by Minnesota, Wisconsin, Michigan, and Ontario to the north, Lake Superior also claims the title of the world’s largest freshwater lake by surface area, a remarkable achievement.

The vast volume of water in Lake Superior eventually flows through the other Great Lakes, ultimately reaching the Atlantic Ocean.

2. Lake Huron (23,000 sq mi / 60,000 sq km)

Huron, the second-largest of the Great Lakes, is bordered by Michigan on the U.S. side and Ontario on the Canadian side.

With 30,000 islands, Lake Huron earns another distinction: it boasts the longest shoreline among the Great Lakes. Its name originates from the French colonists’ term for the Indigenous Wyandot people.

3. Lake Michigan (22,300 sq mi / 58,000 sq km)

Lake Michigan, the third-largest of the Great Lakes and the third-largest in the U.S., is hydrologically connected to Lake Huron via the Straits of Mackinac, sharing the same surface elevation. This connection allows them to be considered a single body of water.

This fascinating fact means that, hydrologically speaking, Lake Michigan-Huron (as they are sometimes referred to) forms the largest freshwater lake in the world by surface area.

4. Lake Erie (9,910 sq mi / 25,700 sq km)

Lake Erie, the fourth-largest of the Great Lakes, is bordered by Ontario to the north and the U.S. states of Michigan, Ohio, Pennsylvania, and New York to the south. It holds the distinction of being the southernmost of the Great Lakes.

The Erie Canal, named after the lake, linked Lake Erie to the Hudson River, revolutionizing trade in North America. However, it also facilitated the spread of invasive species, which adversely impacted native species like the lake trout.

5. Lake Ontario (7,340 sq mi / 19,000 sq km)

Lake Ontario, the fifth and easternmost of the Great Lakes, serves as the final stop for water flowing through the Great Lakes system before it reaches the Atlantic Ocean via the Saint Lawrence River.

The U.S.-Canada border runs directly through the center of Lake Ontario, with Canada to the north and New York State to the south.

Lake Ontario derives its name from the Wyandot language, where it translates to "great lake." Like the other Great Lakes, it was formed during the last ice age approximately 14,000 years ago.

5 Largest Man-Made Lakes in America

While humans have demonstrated remarkable ingenuity in reshaping nature, our creations pale in comparison to the natural grandeur of the Great Lakes. Nevertheless, through damming rivers and lakes, we’ve managed to create some notable artificial water bodies.

Below is a list of the five largest man-made lakes in the U.S. A reservoir, technically a dammed lake, often sees an increase in surface area and volume. While it’s possible to create a lake from scratch, such instances are rare and typically result in smaller bodies of water.

1. Lake Oahe (578 sq mi / 1,500 sq km)

Spanning North and South Dakota, Lake Oahe is the largest artificial lake in the U.S. Created by the Oahe Dam, it impounds a section of the Missouri River, forming an extensive freshwater reservoir.

2. Lake Sakakawea (575 sq mi / 1,489 sq km)

Situated in the Missouri River basin, Lake Sakakawea was formed by the construction of the Garrison Dam in North Dakota during the 1950s by the U.S. Army Corps of Engineers.

3. Red Lake (444 sq mi / 1,250 sq km)

Red Lake, located in Minnesota, is renowned as a prime ice fishing destination and supports native fish species like bluegill, lake sturgeon, and yellow perch.

4. Fort Peck Lake (383 sq mi / 992 sq km)

Situated in Montana, Fort Peck Lake was created by the Fort Peck Dam on the Missouri River. It is part of the Charles M. Russell National Wildlife Refuge, making it a popular spot for tourists and a haven for numerous bird species.

5. Truman Lake (327 sq mi / 847 sq km)

Truman Lake, located in Missouri, ranks as the fifth-largest artificial lake in the U.S. Unlike many reservoirs designed for drinking water storage, its primary purpose is flood control, with additional roles in recreation and hydroelectric power generation.

Biggest Lakes in Each U.S. State

The United States is home to an abundance of lakes, as highlighted earlier. Every state boasts its own lakes, and below is a compilation of the largest in each, measured by surface area. It’s important to note that a significant number of these lakes are man-made.