Charles Ulrick Bay (September 5, 1888 – December 31, 1955) was an American businessman and diplomat.

Bay operated an oil company and served in the Office of Strategic Services.

Bay was a politically appointed ambassador and was nominated for the embassy mission by President Harry S. Truman.

[3] Bay had family ties to Norway and special interest in American - Norwegian relations as an ambassador.

He was much in favor of Norwegian membership in NATO and economic cooperation in many ways between the United States and Norway.