The community was founded by Quakers who arrived in the early 18th century searching for land where they could grow tobacco and corn. One of the very early land owners in the Sandy Spring area was Richard Snowden, who patented (purchased) the "Snowden's Manor" in 1715. Snowden gradually enlarged his property with additional land purchases over the next few decades until it was surveyed at over as "Snowden's Manor Enlarged" in 1743. Another important early landowner, Major John Bradford, had patented over in the Sandy Spring area, including "Charley Forest" in 1716, "Charley Forest Enlarged", "Higham", and "Discovery." Bradford sold off large parts of these properties, but Snowden's son-in-law, James Brooke, later bought up the original Charley Forest land as well as other land in the area, eventually owning over by the 1760s. The Sandy Spring Library opened behind the Sandy Spring Store in 1842. The Farmer's Club of Sandy Spring was established in 1844 to discuss preferable methods of farming.
A 1901 Department of Labor study documented hundreds residents who trace their lineage 125 years to free black families.
The Quakers built their meeting house in 1814 near a fresh-water spring that gave its name to the community. In the late 19th century the community started a local school called the Sherwood Academy. This school was turned over to the Government of Montgomery County in 1906 to become Sherwood High School, the county's third public high school. A Quaker school, Sandy Spring Friends School, was established in 1961.
Sandy Spring's boundaries are roughly Brooke and Dr. Bird roads to the north and west, Ednor Road to the south, and New Hampshire Avenue to the east.
The United States Census Bureau combines Sandy Spring with the nearby community of Ashton to form the census-designated place of Ashton-Sandy Spring, and all census data are tabulated for this combined entity.