This is where you can mail letters and packages, or buy postage. This location is open year-round.

Operating Hours

• Open Monday–Friday, 8:30 am–5 pm
• Closed US federal holidays
• Lobby open 24/7

Accessibility

Designated accessible parking in front. Wheelchair-accessible; entrance on south side of building.

Bear Sculptures

The two bears at the post office entrance were added in 1941 and commissioned by the Federal Works Agency to enhance federal buildings with artwork. Gladys Caldwell Fisher sculpted the cubs from Indiana limestone based on her observations of grizzly bears at one of the feeding grounds then permitted in the park. The three-ton bears were shipped by rail from Denver to Gardiner, Montana.

National Register of Historic Places

The Mammoth Hot Springs post office was listed on the National Register of Historic Places in 1987 with 11 other Wyoming post offices built from 1908 to 1939. The buildings were said to “record the evolution of both the political/economic philosophies and the design philosophies of the federal government” during a period when building design was used “to provide a symbol of the monumental presence of the federal government in its post offices.”

Yellowstone’s main post office was one of 1,007 post offices constructed from 1935 to 1938 “with a view to relieving countrywide unemployment.” The Yellowstone Post Office is a concrete building with a hipped roof in the French Renaissance Moderne style, compatible with the Art Moderne style ornament on the nearby Mammoth Hot Springs Hotel, which was partially rebuilt in 1936. The post office lobby has walls of travertine from a private quarry.