The LNER Class K1 is a type of 2-6-0 (mogul) steam locomotive designed by Edward Thompson. Thompson preferred a simple two-cylinder design instead of his predecessor Nigel Gresley's three-cylinder one.

Seventy K1s were built based on the prototype K1/1 which was made from a converted class K4 locomotive (number 3445 MacCallin Mor) which was rebuilt in 1945. Peppercorn ordered the 70 locomotives of Thompson's design from the North British Locomotive Company of Glasgow. They were the last steam locomotives built to an LNER design, although all were delivered under British Railways auspices. Numbered 62001–62070 they entered service between May 1949 and March 1950.

One has been preserved.