The largest ever lotto jackpot occured in 2012 in the US. There was no winner for the Mega Million jackpot 18 consecutive times in a row so the jackpot rose to a record 656 US Dollar.
The record jackpot was finally hit on March 30, 2012. There were three winning tickets. The winners came from Maryland, Illinois and Kansas. Before the winners came forward a 37 year old mother of seven claimed that she had won but misplaced her ticket. She later admitted that she didn't actually remember if she had the right numbers on her lottery ticket.
Mega Millions is also responsible for the second-largest jackpot ($390 million in 2007) and the the third-largest jackpot ($380 million in 2011) in history.