The 19th annual Polar Plunge was held at the North Avenue Beach in Chicago.
Lake temps was 32 degrees, however the air was colder. Real feel temps were in the single digits.
The event has raised millions of dollars for the Special Olympics.
The money is used to fund events and activities year-round for the organization's 7,500 athletes.
"Our money raised here in Chicago actually stays with the Chicago Park District and Chicago Public Schools and works on our programming for the athletes," said Heather Kundert, executive director of the Special Olympics. "And I think something that people don't realize we do, we provide them meals and transportation because a lot of the families can't necessarily get their athletes to and from sports."
Celebrities and public figures including Mayor Rahm Emanuel have taken part in the event in the past.