St Charles, MO - The St. Charles County Election Authority reminds residents that October 11 is the last day to register to vote and be eligible to vote in the November 7 General Election. St. Charles County residents can register at any local library, any Department of Motor Vehicles location, or at the Election Authority office located in the St. Charles County Administration Building at 201 N Second Street in St. Charles. St Louis City and County residents may also check with any local library, any Department of Motor Vehicles location, or at an Election Authority office.