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If you've been issued this type of government ID, you have to use it in order to register to vote. If you don't have a Colorado driver's license or identification card, you can still register by providing the last 4 digits of your Social Security number. Make a photocopy of this ID if you plan to vote by mail. You may be required to submit it along with your mail-in ballot. You only need to be at least 16 years old to register, but you must turn 18 by Election Day in order to vote. It's fine if your 18th birthday falls on Election Day itself, as long as you'll be 18 years old when you go to cast your ballot. You can register to vote at any point after you turn 16; there doesn't have to be a specific election that you intend to vote in in order to register. by Election Day, if necessary. You have to be an American citizen in order to register to vote in Colorado. If you have birthright citizenship or you're already naturalized, you can skip this step. You don't need to live in any specific precinct or area; you just need to have been a Colorado resident for 22 days. Note that this 22-day period must be the period immediately before the election. For example, if an election were taking place on January 23, you would need to have lived in Colorado from January 1 to January 22. You'll have to wait until you're no longer incarcerated before you can register to vote. You can register if you're currently on parole, but you won't be able to vote until you've completed your sentence. If you were previously registered and then were sentenced to incarceration for a felony conviction, you'll have to re-register to vote. You can still register to vote if you're only in jail for a misdemeanor sentence.
Check to see if you have a Colorado State driver's license or ID card. Make sure you'll be 18 years old by the date of the election. Become an American citizen Reside in Colorado for 22 days before the election. Note that people in prison for a felony conviction are ineligible to vote.