State Route 261 (SR 261) is a tollway in the U.S. state of California that is part of the Eastern Transportation Corridor system. It connects State Route 241 with Interstate 5. However, Route 261 does not directly connect with I-5; surface streets must be used to make the connection; continuing south on Route 261 leads directly into a high-speed controlled-access portion of Jamboree Road.

SR 261 is part of the California Freeway and Expressway System.

The southern end of SR 261 is at an interchange with Jamboree Road near Walnut Avenue. SR 261 passes under I-5 but does not have an interchange with it. The freeway continues next to The Market Place, a mall in Irvine, before going through a toll plaza after the Irvine Boulevard interchange. Following this is the Portola Parkway exit, after which SR 261 briefly enters the city of Orange and has an interchange with Santiago Canyon Road (CR S18). In the middle of this interchange, SR 261 merges with SR 241; the latter continues north towards SR 91.

Except where prefixed with a letter, postmiles were measured on the road as it was in 1964, and do not necessarily reflect current mileage. The entire route is in Orange County.