CT is publicly funded, financed through sales taxes, federal grants, and farebox revenue, with an annual operating budget of $231.6 million as of 2024[update].

The system, officially the Snohomish County Public Transportation Benefit Area Corporation (SCPTBA), operates a fleet of 282 accessible transit buses, 52 paratransit vehicles, and 362 vanpool vans, maintained at two bus bases in Everett.

Renamed Community Transit in 1979, the agency expanded service in its first decades of existence, later taking over King County Metro commuter routes to Seattle in 1989 and adding several cities into its PTBA in the 1980s and 1990s.

The agency operated commuter service directly to destinations in Seattle until September 14, 2024, shortly after Link light rail was extended to Lynnwood City Center station.

CT was the first operator of bus rapid transit in Washington state and introduced "Double Tall" double-decker buses on its commuter routes to Seattle in the early 2010s.

[12][13] The PTBA plan for a countywide bus system was approved during a general election on June 1, 1976, funded by a three-tenths increase of the sales tax rate in member cities.

[21] SCPTBA Public Transit began operating in the cities of Brier, Edmonds, Lynnwood, Marysville, Mountlake Terrace, Snohomish and Woodway on October 4, 1976,[22] using 18 leased GMC buses on seven routes carrying 6,414 passengers without fares during the first week.

[29][30] Early on, the busiest local line was Route R14, accounting for 21 percent of system ridership in the first three months, running from the Edmonds waterfront to Lynnwood and the Boeing Everett Factory.

[25][32] CT continued to grow through the end of the decade, annexing the cities of Arlington, Lake Stevens, Monroe, Granite Falls, Mukilteo, Stanwood and Sultan into the PTBA by 1980;[26][33] the bus system had the largest growth in ridership within the state in 1980, with local routes gaining 68.3 percent more riders and Metro-operated "Cream Buses" to Seattle gaining 21.4 percent more riders.

[35] The annexations of outlying communities in northern and eastern Snohomish County and the completion of park and rides in Edmonds and Mountlake Terrace saw ridership rise to over 3 million passengers by 1983.

[40] The move to a private carrier was opposed by both Metro and the Amalgamated Transit Union,[41][42] but the introduction of 49 air conditioned coaches by ATE led to a 25 percent increase in ridership by January 1987.

Detectives from the FBI and Snohomish County Sheriff seized records from both parties and began a two-month audit of Community Transit management.

[50] The auditors released a report that criticized the management style of Executive Director Ken Graska and his department heads, leading to the former's resignation in December 1993 after nine years at his position.

[52] A U.S. District Court jury found Woodall guilty of 15 counts of mail fraud in December 1996,[53] with Judge John C. Coughenour sentencing him to 2.5 years in federal prison the following May, along with Ed's Transmission being forced to pay a $825,000 settlement after a civil suit was filed.

[56] In 1990, a second proposal was rejected by the Everett City Council after consultants determined that a merger would only save $350,000 per year in deadheading for Community Transit and that both staffs would need to be retained because of the lack of service duplication between the two agencies.

[64][65] The two agencies further collaborated with Sound Transit and the Washington State Department of Transportation in the construction of the South Everett Freeway Station the following year.

[66] In their most recent expansion in 1997, the Snohomish County PTBA annexed the Eastmont and Silver Firs census-designated places between Everett and Mill Creek, as well as the Tulalip Indian Reservation west of Marysville.

[73] With the service cuts, CT began its VanGO program to donate its retired paratransit minibuses to nonprofit organizations in Snohomish County instead of auctioning them off.

[78] Community Transit introduced its current logo and slogan in 2005, replacing an older one in use since 1986 and retaining its blue-and-white color scheme, as part of the roll-out of the first New Flyer Invero buses in the United States.

[81][82] The pilot project was deemed a success and expanded into the "Surf and Ride" program on all Route 422 trips in 2006, as well as select trips on Routes 406 and 441 from Edmonds to Seattle and Overlake on the Eastside, respectively; the Wi-Fi program was canceled in 2010, with the removal of equipment in buses brought on by low customer response, budget constraints and the adoption of improved cellular networks that support mobile browsing on smartphones.

[96] In June 2015, CT restored its Sunday and holiday service as part of a 27,000-hour expansion, representing 20 percent of the 2010 reduction, funded by recovering sales tax revenue and a 25-cent increase in fares the following month.

[117] Sound Transit funded several capital projects to improve bus service on the Interstate 5 corridor, including direct access ramps from HOV lanes to Lynnwood and Ash Way park and rides that opened in 2004 and 2005, respectively.

[120] Commuter rail service to Snohomish County on the Sounder North Line began in December 2003 with a single round-trip connecting Everett and Edmonds to King Street Station in Seattle during rush hour.

On September 14, Community Transit debuted its redeveloped bus network and eliminated all of its Downtown Seattle express service in favor of new commuter routes connecting to Lynnwood and Mountlake Terrace stations.

[8]: 19–20 [142] The largest facilities, primarily located in southwest Snohomish County, include weatherproof bicycle lockers in addition to automobile parking.

It operates similar to ride-hailing service with fixed fares (including payment via ORCA cards) and is available to all members of the public; trips are requested through an app or phone call.

The card also allowed free transfers within a two-hour period between transit agencies of equal value, with the difference for higher fare subtracted from the e-purse or prompting for cash.

[134][166] In addition to its bus fleet, Community Transit maintains 333 vans for its vanpool program and 52 paratransit minibuses equipped with wheelchair lifts for dial-a-ride service.

[171][172] The 42-foot-long (13 m), 14-foot-high (4 m) Enviro500 seated 77 to 81, with standing room for 20 additional passengers, replacing the capacity of the standard articulated buses used on the commuter routes in a smaller footprint.

[179][180] Sound Transit plans to eventually replace its entire Snohomish County fleet with double-deckers in the near-term future,[181] beginning with 32 additional buses in 2018.