The Chrysler 300 "letter series" are high-performance personal luxury cars that were built by Chrysler in the U.S. from 1955 to 1965 and were a sub-model from the Chrysler New Yorker. After the initial year, which was named C-300 for its standard 300 hp (220 kW) 331 cu in (5.4 L) FirePower V8, the 1956 cars were designated 300B. Successive model years were given the next letter of the alphabet as a suffix, reaching the 300L by 1965, after which the model sequence was discontinued while the "300" remained. At its introduction it was advertised as "America's Most Powerful Car".

Personal luxury car is a North American car classification describing somewhat sporty, sophisticated mass-market coupés that emphasized comfort over performance. The North American manufacturers most often combined engineering, design, and marketing to develop upscale, distinctive "platform sharing" models that became highly profitable.