The 30-year-old was caught on camera driving at 87 miles (140 kilometres) per hour in a 50 mph zone on a motorway near Liverpool, northwest England, on July 1 last year.
But his lawyer Nick Freeman told magistrates in the city that the prosecution had not followed procedures correctly. The prosecution then said they would offer no evidence against the Lancashire player.
Freeman, who has earned the nickname "Mister Loophole" for exposing procedural discrepancies in speeding cases often involving high-profile figures, said outside court that the prosecution notice arrived on July 19.
"It is fundamental in any speeding case that the notice is sent and received within 14 days," he added.
Flintoff, who has been plagued by injury in the last year, said nothing to waiting media but Freeman said his client was "relieved" at the decision and could now concentrate on his cricket.