Excepting several managerial and maintenance positions, Unitrans is managed and operated entirely by students of the University of California, Davis who usually work part-time while attending school.

The system is well known throughout the area for its use of several distinctive ex-Transport for London double-decker buses, as well as its fleet of modern natural gas single-decks.

These students approached Davis' then-mayor Maynard Skinner and appealed for support both politically and financially.

[4] To be unique, get the system noticed, and encourage ridership, Unitrans made arrangements to purchase two former London Transport double-decker buses in the middle part of 1967 and use them on "East" and "West" perimeter routes in Davis.

According to the March 5, 1968 edition of The California Aggie newspaper, the two RTL type double-decker buses cost $3500 each, and were shipped to San Francisco for an additional $1000.

After being modified with features like clearance lights and larger left side mirrors, service began in February 1968.

These first two lines operated from what is now a parking lot behind Young Hall, until 1970 when expanded service forced the terminal to move to its current location near Hickey Gym.

[4] Greater ridership in the 1980s prompted the writing and passing of a student referendum that added a $13 fee to registration costs to create the fare-less system.

In the late 1990s, the remainder of the GM fleet was retired, as were the two Daimlers and RTL1194, one of the first two double-deck buses purchased by Unitrans (although it hadn't operated in some time).

In 2000 the Unitrans maintenance shop completed its retrofit of RT2819 to use a brand-new John Deere natural-gas powered engine.

This bus was eventually introduced on April 20, 2004, when California Governor Arnold Schwarzenegger made a visit to the campus as part of a push for the Hydrogen highway project.

These buses were purchased in coordination with Sacramento Regional Transit, and featured a low floor design, intended to make loading wheelchairs easier on the driver and the passengers.

With the exception of the vintage double-deck buses and two rarely used support vans, the fleet is powered entirely by compressed natural gas.

Unitrans received delivery in March 2010 of two Alexander Dennis Enviro500 buses, in an attempt to accommodate the high passenger loads while reducing the demand on drivers.