* The Charlotte, North Carolina Mint – 1835 to 1861. After the Civil War, the plant was reopened in 1868 as an assay office until 1913, when it was ultimately closed.
* The New Orleans, Louisiana Mint – 1835 to 1942. Coinage operations were conducted here from 1838, but were suspended from 1861 until 1879; assay functions were performed from 1876. Coinage resumed in 1879 and continued until 1909. The facility operated as an assay office from 1909 until 1942, when it was closed.
* The U.S. Assay Office, St. Louis, Missouri – 1881 to 1911
* The U.S. Assay Office, Helena, Montana – 1874 to 1933
* The U.S. Assay Office, Salt Lake City, Utah – 1909 to 1933
* The U.S. Assay Office, Deadwood, South Dakota – 1898 to 1927
* The U.S. Assay Office, Boise, Idaho – 1869 to 1933
* The U.S. Assay Office, New York, New York – 1854 to 1982
* The U.S. Assay Office, Seattle, Washington – 1898 to 1955