- Langdon Cheves Papers, 1777-18642
- Lincoln High School Collection3
- M. Hayes Mizell Papers108
- Mabel Payne Photograph Collection640
- Mamie E. Garvin Fields Papers, 1894 - 19877
- Maps of Columbia and Richland County11
- Maxcy Gregg Papers, 1835-1888.2
- Mayors of Columbia35
- Midlands Memories756
- Midlands Memories
9
- Midlands Memories 1
- Minutes of the Annual Conferences of the Baptist, Episcopal, Lutheran, Methodist, and Presbyterian Churches in South Carolina, 1785-192037
- Miscellaneous South Carolina Pamphlets1
- Modjeska Simkins Papers, 1909-19921
- Modjeska Simkins: In Her Own Words21
- Moth Specimens of Congaree National Park1,297
- Oral Histories from Richland Library49
- Paul Hamilton Papers2
- Pee Dee District Dental Society Records, 1933-19881
- Philip Simmons Collection6