Unclaimed lottery prizes worth a total of $502,000 remain up for grabs in Iowa, with one worth $500,000. Multiple other prizes in the state are set to expire soon. Meanwhile, in Massachusetts, a winner has less than a month left to claim $25,000 per year for life. Unclaimed prizes are relatively common, occurring five to seven times a year, according to lottery officials. Public announcements often help connect winners with their winnings.