National Book Award for Nonfiction

The National Book Award for Nonfiction is one of five US annual National Book Awards, which are given by the National Book Foundation to recognize outstanding literary work by US citizens. They are awards "by writers to writers". The panelists are five "writers who are known to be doing great work in their genre or field". The original National Book Awards recognized the "Most Distinguished" biography and nonfiction books (two) of 1935 and 1936, and the "Favorite" nonfiction books of 1937 to 1940. The "Bookseller Discovery" and the "Most Original Book" sometimes recognized nonfiction. (See below.) The general "Nonfiction" award was one of three when the National Book Awards were re-established in 1950 for 1949 publications, which the National Book Foundation considers the origin of its current Awards series.

From the Wikipedia article “National Book Award for Nonfiction”, licensed under CC BY-SA 4.0.

Check the official rules of the National Book Award for Nonfiction for the current eligibility window, accepted formats, residency or language requirements and any entry fee. For most established prizes the publisher submits on the author's behalf, often with a limit on entries per imprint.

If you are self-published, look for an explicit statement that independently published books are accepted, and budget for entry fees and copies for judges.