Dealer plates were first issued in 1907, in reverse colors with a ‘D’ suffix.
I am not sure when the distinction was made between “New Car Dealer” and “Used Car Dealer”, but I would imagine it was sometime around 1932, when ‘D’ prefixes came into use alongside ‘X’ prefixes.
Before long, they reached “D” dealer 999, and introduced a “Q” prefix.
“Used Dlr” was spelled out for the first time in 1942. With the reflective 1949 plates, just the caption “Used” appeared on the plates.
1954 marked a return to “Used Dlr”, and the new longer plates meant the end of the “Q” prefix. Q-series numbers were remade as “D” numbers, with 1000 added to the old “Q” number.
For 1958, standard-sized 6×12 plates were issued, in white on blue. Beginning in 1961, the date was embossed in in the corner of the plate, and the colors reversed every year – white on blue for even years and blue on white for odd.
The official distinction between ‘New Dlr’ and ‘Used Dlr’ was spelled out on the plates starting in 1942. Corner date tabs were used through 1948
1950. This design, an aluminum plate with reflective yellow scotchlite, came into use for the 1949 expirations. These plates held up very poorly.
After reaching used dealer number D 999, they went to a ‘Q’ prefix.
Perhaps realizing how poorly the reflectorized plates held up, plain, painted steel plates were used for 1952 and 1953.
Larger plates which could accommodate 4 numbers were used for 1954 and 1955.
With the larger plates, the former ‘Q’ prefix plates were remade into the ‘D’ series, but with 1000 added to the number. Thus, the Q/B 118 above and this D/D 1118 are from the same dealer.
Typically the 1956 plates were revalidated with a ’57 tab. It appears that new plates issued in 1957 were still in the old style but had the embossed year omitted.
With the standardized plate size introduced in 1957, dealer plates followed suit. Tabs were used for 1958.
Embossed date, with tab slots for the 1960 tab.
Dealer plates were one of the few dated types in 1961 in Connecticut. While there were no ‘1961’ dated passenger plates, 1961 dealer plates are not inherently any rarer than any other year of dealer plate.
Tab slots are gone, and the colors now reverse every year.
Most 1968 Dealer and Repair plates are terribly rusty. This one isn’t, only because it was never used and is still in its original plastic wrapping.