- Laine family papers, 1772/19617
- Lambert-Sheetz Family Papers, 1818/19071
- Land Grants, 1749/19851
- Land Grants, 1795/18361
- Land Papers Miscellaneous, 1803/19331
- Land Papers from Eastern West Virginia, 1783/1848, bulk 1820/18292
- Landon Duncan Letters, 1812/18373
- Lantz Family Papers, 1814/19212
- Larry Jones, Collector, Postcards, Photographs, and Other Material, 1785/1993, bulk 1897/19931
- Latane Family Papers
1650-189810
- Latin American Map Collection, 1711/18731
- Lawrence Lewis family papers, 1785/18584
- Lawrence Washington collection of Washington family papers, 1787/19321
- League of Women Voters of the Fairfax Area records, 1809/2012, bulk 1978/20121
- Lee Nicholson Papers, 1827/193810