The Thermopolis Main Post Office in Thermopolis, Wyoming was built as part of a facilities improvement program by the United States Post Office Department. The post office in Thermopolis was nominated to the National Register of Historic Places as part of a thematic study comprising twelve Wyoming post offices built to standardized USPO plans in the early twentieth century.

• Photographs of the Thermopolis Post Office at the National Park Service's NRHP database
• Thermopolis Main Post Office at the Wyoming State Historic Preservation Office