Her choice of being the record holder was down to being to one of a few of the A4 class that were built with a double chimney and double Kylchap blastpipe, which made for improved draughting and better exhaust flow at speed. The record run damaged the locomotive as she had to be stopped at Peterborough, but at least the world speed record was in hand. After her world speed record run "Mallard" continued in service with the LNER and British Railways until 1962 when she was withdrawn from service for preservation as part of the National collection of locomotives.

She was restored for display by Doncaster works in the LNER Garter Blue livery with the streamline side valances when she broke the world speed record, first going on display in the then Clapham Transport Museum and then from 1975 in the National Railway Museum in York. In the 1980s with the 50th anniversary of her world speed record in 1988 No. 4468 was restored to operational order for a limited number (25 steamings) of runs on the mainline including some specials between York and Scarborough in July 1986 and a couple of runs between York and Harrogate and Leeds around Easter 1987. In 1988 round the 50th anniversary "Mallard" worked special railtours along part of the famous East Coast Mainline round Doncaster and York and to Scarborough as well as few trips over the Settle and Carlisle line. Her final steaming was in August 1988 on a last run over the Settle and Carlisle line, after this she was withdrawn from service and returned to be on display in the National Railway Museum. She still can be moved on the mainline, hauled by other locomotives as in the 1990s, 2000s and 2010s "Mallard" has visited her birth town of Doncaster for several open days, Locomotion - National Railway Museum at Shildon in Durham and has also visited Barrow Hill Roundhouse in Derbyshire for several Gala events there.

In 2013 No. 4468 "Mallard" celebrated 75 years since achieving the world speed record and to mark this the National Railway Museum put on the Great Gathering which saw all six surviving LNER A4 locos together for the first time since the end of steam in the UK in the 1960s. T he locos involved were No. 60008 "Dwight D Eisenhower", temporarily repatriated from the National Railroad Museum in Green Bay, Wisconsin in the United States of America, No. 60007 "Sir Nigel Gresley", No. 60009 "Union of South Africa", No. 4464 "Bittern", No. 4489 "Dominion of Canada" which was temporarily repatriated from Exporail, the Canadian Railway Museum in Montreal, Canada and of course No. 4468 "Mallard" Since then "Mallard" has continued to be on static display in the National Railway Museum in York, whether the locomotive will steam again is something that only time will tell.