The Helena National Bank was organized in Helena, Montana, in September 1890 by John T. Murphy, S.C. Ashby, A.B. Clements, and Frank Baird. In October 1893 the bank merged with the Second National Bank, and E.D. Edgerton became president. This combined bank in turn merged with the First National Bank in January 1895. Records (1890-1895) include correspondence; financial records; legal documents; organizational records; and miscellany.

The Second National Bank of Helena, Montana, headed by Erastus D. Edgerton, opened in 1882 and merged with the Helena National Bank in 1893 as a result of the financial panic. Collection (1881-1896) includes correspondence, court papers, financial records, legal documents, organizational records, and miscellany.