- Arah J. Evans Autograph Album, 1849/19531
- Archibald W. Campbell (1839-1899), Newspaperman, Papers, 1855/1941, bulk 1855/18993
- Archibald Woods Papers, 1777/1846, bulk 1783/18465
- Aretas Brooks Fleming (1839-1923) Papers, 1784/19241
- Aretas Brooks Fleming Papers, 1784/19241
- Armistead Boothe Papers (MS164), 1803/199012
- Armistead Papers, 1736/18971
- Armistead-Cocke Papers, 1680/19177
- Armstead L. Robinson papers, 1848/2001, bulk 1967/19927
- Armstrong Family Papers, 1853/19031
- Arnaud Preot Collection, 1841/18603
- Arthur I. Boreman Papers, 1830/194921
- Asa F. Horn Account Book and Family Correspondence, 1854/18612
- Ashcraft Family Genealogy, 1732/19721
- Association for the Preservation of Virginia Antiquities, Montgomery County Branch Papers, 1754/1996, bulk 1958/19831