Westminster is on several state highways: I-25, US 36, US 287, SH 95, SH 121, and SH 128.
The Denver Regional Transportation District (RTD) provides bus service to Westminster and the rest of the metropolitan area. RTD plans to build commuter rail servicing Westminster as part of the Fastracks project that originate in Denver and travel to Longmont and Boulder respectively.
As part of the US 36 Express Lanes Project, a bus rapid transit line was established along the corridor, branded the Flatiron Flyer. The BRT line was completed in 2016, and consists of six stations along US 36, including two in Westminster, Church Ranch Station and Westminster Center Station. The busses travel on managed lanes to increase the efficiency of the service, and offer frequent bus service connecting the Denver metro area with the northwest region’s businesses, federal institutions and the University of Colorado–Boulder. Riders also have convenient and frequent access to downtown Boulder and downtown Denver.
Westminster is served by Denver International Airport and nearby Rocky Mountain Metropolitan Airport.