Canberra buses have featured six distinct styles of registration plates.
(to date, only three plates – C.94, C.137 and C.166 – are known). It is possible that the authorities re-issued plates, as C.137 was a 1926 AEC Renown while C.166 was a Dodge Bros with Graham char-a-banc body delivered no later than 1925.
February 1927 Plates
These plates, which were issued under the ACT Motor Ordinance. Plates from CO.1 to at least CO.31 are known to have been issued.
C Series Plates
The ‘C’ series plates issued to all Commonwealth vehicles from the 1930s to the 1950s. Apart from Canberra’s buses, buses used for the public bus service in Darwin, at the Woomera research facility and by the Post Master-General’s Department for transport of field staff were also registered in this series.
The Special C Series Plates
The special ‘C’ series plates (C.xxxx) reserved for Canberra buses and first issued to coincide with the delivery of the ComEng bodies AEC Reliances in 1956. Canberra buses delivered prior to 1956 were not reregistered in the new series.
ZIB Series Plates
the ZIB series which were issued from 1961-62. These plates continued the number series introduced with the C.xxxx plates. All vehicles from the 1956 series still in the fleet were reregistered. The Z stands for Commonwealth, the I for Interior and the B for Bus.
BUS Series Plates
Following the ACT gaining self-government in 1988, all ACT Government vehicles bearing Commonwealth Plates had to be re-registered, including Buses which featured the ZIB Plates. As a result, the ACT Government ‘BUS’ plates were introduced in 1988. These plates also continued the number series introduced with the C.xxxx and ZIB plates. It was initially suggested that bus registrations would start at 1-000 with either an MO or B prefix however this did not eventuate.