The state government said the completion of the M2 motorway upgrade and new technology had resulted in faster travel times.
Hornsby MP Matt Kean said recent improvements to bus timetables in The Hills had improved running times for a number of services.
"Bus services from Dural and Cherrybrook on routes 620X, 621, 622, 642 and 642X will have improved timetables which take advantage of the completion of the M2 motorway upgrade and new technology which allows bus planners to more accurately predict travel times," Mr Kean said.
"West Pennant Hills customers using routes 635, 650, 650X, 651, 652X and 653 also have improved times."
An additional route 621 service from Macquarie Park to Cherrybrook in the afternoon has also been added.