Some of the lines serve the Los Angeles County border communities of Lakewood, La Mirada, Cerritos, Artesia, Hawaiian Gardens, and Long Beach.

In 2005, OCTA was judged America's Best Public Transportation System by the American Public Transportation Association, for its record gains in bus and Metrolink commuter trains ridership that it operates or funds.

Cal State Long Beach El Camino Real & Avenida Santa Margarita Newport Transportation Center (short line) Fullerton Park & Ride Pacific Coast Hwy & 1st St Fullerton Park & Ride Lemon Dr & Main St Beach Bl & La Habra Bl Pacific Coast Hwy & 1st St Buena Park Metrolink Station Los Cerritos Center Esperanza Rd & Fairlynn Bl Fullerton Park & Ride Pacific Coast Hwy & Magnolia St Fullerton Park & Ride 19th St & Meyer Pl 1st Av & Euclid St MacArthur Bl & Hyland Av Los Cerritos Center Esperanza Rd & Fairlynn Bl Carson St & Norwalk Bl The Village at Orange Electric Av & Main St Berkeley Av & Harbor Bl Harbor Bl & Bernard St Norwalk Bl & Wardlow Av The Village at Orange Fullerton Transportation Center Balboa Bl & 23rd St Cal State Long Beach The Village at Orange Anaheim Regional Transportation Intermodal Center Yale Loop & Alton Pkwy MacArthur Bl & Main St (short line) Chapman Av & Valley View St Santiago Canyon College (Mon-Sat) Rancho Santiago Bl & Chapman Av (Sun) Flower St & 6th St Newport Transportation Center Chapman Av & Valley View St (early AM / late PM) Belgrave Av & Valley View St Brea Mall State College Bl & Via Burton (short line) Anton Bl & Sakioka Dr (short line) UC Irvine (weekdays) The District (weekends) Cal State Long Beach Main St & Locust St (weekends) Fruit St & Tustin Av (weekends) Westminster Mall Larwin Square Goldenwest Transportation Center Irvine Valley College Bryan Av & Newport Av (short line) Warner Av & Pacific Coast Hwy Tustin Metrolink Station UCI Health–Placentia Superior Av & Placentia Av Warner Av & Pacific Coast Hwy Tustin Metrolink Station Talbert Av & Beach Bl John Wayne Airport Newport Transportation Center Foothill Ranch Towne Center Plano Trabuco Rd & Alas De Paz Fullerton Park & Ride Laguna Hills Transportation Center Niguel Rd & Crown Valley Pkwy Portola Plaza South Coast Plaza Oso Viejo Community Park Avenida Empresa & Aventura Niguel Rd & Crown Valley Pkwy Laguna Beach Bus Station Tustin Metrolink Station Golden Lantern & Dana Point Harbor Dr Laguna Hills Transportation Center Calle de Los Molinos & Avenida Pico Routes with numbers in the 100s descended from the old RunAbout service that formerly served residential neighborhoods, or provide service to portions of 1-99 routes that have reduced demand.

Anaheim Canyon Metrolink Station Goldenwest Transportation Center Beach Bl & La Habra Bl Kraemer Bl & Coronado St Beach Bl & La Habra Bl Brea Mall Flower St & 6th St The Village at Orange UC Irvine Foothill Ranch Towne Center Laguna Hills Transportation Center Yorktown Av & Goldenwest St UC Irvine Routes with numbers in the 400s are "StationLink" and Irvine Shuttle (iShuttle) routes which travel between Metrolink stations and business districts.

Tustin Metrolink Station Tustin Metrolink Station 2101 Business Center Irvine Transportation Center Irvine Center Dr & Sand Canyon Av Orange Transportation Center La Veta Av & Pepper St Tustin Metrolink Station Food and Drug Administration Tustin Metrolink Station UC Irvine Irvine Transportation Center Lake Forest Dr & Regency Ln Routes with numbers in the 500s are "Rapid" routes that operate on heavily used routes making limited stops and at transfer points to other routes.