The Colorado Secretary of State's complete 2018 Election Calendar
may be found here
January 8, 2018 - Last day to affiliate with the Republican Party or Democratic Party in order to vote in their March 6th Party precinct caucuses
February 5, 2018 - Last day to change your voter registration address in order to reside in the precinct for 30 days, a requirement to vote in a specific precinct for the March 6th Party precinct caucuses
March 6, 2018 - Republican Party and Democratic Party Precinct Caucus Day
June 26, 2018 - Primary Election Day. All ballots must be received by 7:00 p.m.
September 22, 2018 - Last day to send ballots to overseas and military voters
October 15, 2018 - Last day to register to vote as part of a registration drive
October 15, 2018 - Ballots mailed to voters during this week
October 22, 2016 - Minimum number of Voter Service and Polling Centers open during this week
November 3, 2018 - Ballot Drop Off locations open during this week
November 6, 2018 - General Election hours 7:00 a.m. - 7:00 p.m. Ballots must be received by 7:00 p.m.
November 6, 2018 - Overseas and military voters must send ballots by 7:00 p.m. Ballots must be received by 8 days after election
You may also register to vote and vote on election day