To register to vote in Arizona you must meet the following qualifications (A.R.S. § 16-101):

• Be a citizen of the United States of America
• Be a resident of Arizona and the county listed on your registration
• Be 18 years of age on or before the day of the next regular General Election

You cannot register to vote in Arizona if (A.R.S. § 16-101):

• You have been convicted of a felony and have not yet had your civil rights restored. For a first-time felony conviction, civil rights are automatically restored upon completion of a person’s sentence and payment of any restitution.
• You have been adjudicated incapacitated by a court of law.