Young Voter Registration – Get Your 16 and 17 year old Registered!! Colorado voter registration rules implemented by the Secretary of State (SOS) allow for young people aged 16 and 17 to pre-register. All they need is a valid social security number or driver’s license. Go to the SOS website at www.govotecolorado.com to get those young people aged 16 and 17 to pre-register. They automatically become a registered Colorado voter upon their 18th birthday.