The first OB chassis rolled out of Bedford's factory in August 1939 however production only lasted two month's before the outbreak of World War II resulted in the cessation of manufacture resulting in just 73 pre-war chassis being produced. During the war years Bedford produced an utility version of the OB chassis known as the OWB.

Production of the OB resumed in October 1945, the early post war period saw a boom in coach & bus travel, and the OB played a major part in fulfilling both operators and passengers requirements between 1946 & 1951. The OB chassis was bodied by a large array of coach builder however the most popular choice by far was the Duple Vista coachwork which was fitted to the vast majority of UK coach versions.

Although the OB is most commonly identified as a coach, the model was also used by some operators as a small capacity bus, most of the vehicles acquired for this type of work received custom bodywork, although in later years some coach versions were downgraded to this work by some operators.

The OB chassis also proved popular with overseas operators, with examples going to operators in places such as Ceylon (now Sri Lanka), Kenya, Australia, New Zealand, Holland, Switzerland & Belgium.

Production finally ended in November 1950 a month after Bedford announced the new SB chassis at that years London Commercial Motor Show. Duple delivered their last Vista bodied OB's in the Spring of 1951. In total over sixteen thousand 'O' Series passenger chassis were produced between 1939 and 1950, over half of which were produced during the wartime years.

The Bedford OB very much represents the heyday of British Coach Travel, these small 27 or 29 seat coaches proved the ideal vehicle for many operators in the early post war years. This classic coach was a familiar sight across the UK from the mid 40's until the early 60's and even today many active examples still exist in the hands of preservationist's today.

After introduction into the range in 1995, nearly 20 releases appeared within the first 2 years, making this the must numerous of the coach models. The number of releases has now reduced to around one per year.

Photographs of the models suggest a modfied longer radiator grille was produced & fitted to models released from early 1996 onwards, the original version appears to be slightly shorter with a gap between its lower edge and the top of front bumper, and was only fitted to models 20101-7/9/10.

Following EFE's acquisition by Bachmann, the model was slightly updated with the addition of driving mirrors. The first EFE Road issues (E20141-6) were released in January 2025 to tie in with the 85th Anniversary of the Bedford OB.