State Route 124 (SR 124) is a state highway in the U.S. state of California that runs in Amador County from State Route 88 south of Ione to State Route 16 near Waits Station.

State Route 124 begins at SR 88 south of the city of Ione. SR 124 continues north as Church Street into the city of Ione, intersecting with Buena Vista Road and passing a lake along the way. Heading northward, SR 124 enters the downtown area of Ione, briefly running concurrently with SR 104 as Main Street before turning northwest as Plymouth Street. In Ione, the route passes a golf club to the west and a reservoir to the north, while heading towards the northeast. SR 124 runs slightly to the northeast as Plymouth Highway, crossing over several creeks, including Mule Creek, and bends slightly towards the east. The highway crosses Horse Creek and Dry Creek, and shortly before re-establishing a northerly route, it passes a mountain known as Rocky Point. SR 124 passes another peak before terminating at SR 16 northwest of Amador City at a T-shaped intersection.

SR 124 is part of the California Freeway and Expressway System, but is not part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration.

Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, based on the alignment that existed at the time, and do not necessarily reflect current mileage. R reflects a realignment in the route since then, M indicates a second realignment, L refers to an overlap due to a correction or change, and T indicates postmiles classified as temporary (for a full list of prefixes, see California postmile § Official postmile definitions). Segments that remain unconstructed or have been relinquished to local control may be omitted. The entire route is in Amador County.

Location	Postmile	Destinations	Notes
​	0.00	SR 88 – Jackson, Clements, Stockton	South end of SR 124
Ione	2.29 R5.96	SR 104 east (Main Street) – Jackson	South end of SR 104 overlap
	R5.77 R2.29	SR 104 west (Preston Avenue) / Shakeley Lane – Galt, Sacramento	North end of SR 104 overlap
​	R10.33	SR 16 to SR 49 – Placerville, Plymouth, Sacramento	North end of SR 124
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus

• California Roads portal

• Caltrans: State Route 124 highway conditions
• Caltrans Traffic Conditions Map
• California Highway Patrol Traffic Incidents
• California Highways: Route 124
• California @ AARoads.com - State Route 124