The start time of "The Late Late Show" depends on which version you are referring to:

• The American version, "The Late Late Show with James Corden," aired on CBS from Monday to Friday nights at 12:37 a.m. ET/PT. It premiered on March 23, 2015, and its final episode aired on April 27, 2023

• The Irish version, simply called "The Late Late Show," is the world's second longest-running late-night talk show and airs live on RTÉ One on Friday nights at 9:30 p.m. It originally premiered on July 6, 1962, at 11:20 p.m. and has maintained a similar late-night timeslot since then

So, the American "Late Late Show" typically started at 12:37 a.m., while the Irish "Late Late Show" starts at 9:30 p.m. on Fridays.