It is 140.3-mile-long (225.8 km) and travels through portions of Tattnall, Toombs, Montgomery, Treutlen, Emanuel, Burke, and Richmond counties in the southeastern and east-central parts of the U.S. state of Georgia.

SR 56 begins at an intersection with US 280/SR 30 (West Brazell Street) in Reidsville, in Tattnall County.

It travels to the west, crossing over the Ohoopee River, and enters Toombs County.

Just before an interchange with Interstate 16 (I-16; Jim Gillis Historic Savannah Parkway), the two highways have an intersection with SR 86.

They curve to the north-northeast and enter Gillis Springs, where US 221/SR 56 intersect the southern terminus of SR 171.

The highway continues to the northeast and intersects US 1/SR 4 (South Main Street), just before entering Swainsboro.

Farther to the northeast, it crosses over the Ogeechee River into Burke County and Midville.

The three routes head east-northeast into town and curve to the northeast to an intersection with US 25/SR 121 (Liberty Street).

Then, it curves around Southland Timber Lake, and meets the western terminus of SR 56 Spur (River Road).

It heads north and northwest, to meet the southern terminus of the now decommissioned SR 56 Spur (Tobacco Road), which leads to Augusta Regional Airport.

The route continues to the north-northwest, and curves to the northwest, until it meets its northern terminus, a second intersection with US 25/SR 121 (Peach Orchard Road) in the southern part of Augusta.

[1] The only portion of SR 56 that is part of the National Highway System, a system of routes determined to be the most important for the nation's economy, mobility, and defense, is the portion in Augusta that is north of Tobacco Road.

Then, at the eastern terminus of Tobacco Road, it turned north onto Doug Barnard Parkway.

After a crossing over Rocky Creek, a curve to the northeast, and a crossing over Butler Creek, it had a curve to the northwest just before it met its northern terminus, an intersection with US 1/US 25/US 78/US 278/SR 10/SR 121 (Gordon Highway) in the central part of Augusta.