In Arizona, the age of majority is 18. On that birthday state law treats you as an adult: your parents lose legal authority over you, juvenile court no longer has jurisdiction, and you gain the rights and responsibilities that come with every other adult in the state.1Arizona Legislature. Arizona Revised Statutes Title 1, Section 1-215 – Definitions A few things still wait until 21, and a narrow set of situations either move the line earlier or keep it from applying cleanly at all.
How Arizona Law Defines an Adult
Arizona Revised Statutes Section 1-215 sets the definition in two places. Subsection 3 defines “adult” as a person who has reached 18, and subsection 19 defines “majority” as 18 years of age or more.1Arizona Legislature. Arizona Revised Statutes Title 1, Section 1-215 – Definitions There’s no gradation and no waiting period. The day you turn 18, the label changes.
What You Can Do at 18
You can sign a binding contract on your own. That covers leases, loans, bank accounts, and real estate transactions. Before 18 most contracts a minor signs are voidable; after 18 you’re bound by what you agree to, with narrow exceptions for fraud or duress.
You make your own medical decisions. Parents no longer authorize treatment or access your records. Under HIPAA, you control who sees your medical information, and a parent who wants to stay involved needs a written authorization from you.2HHS.gov. Personal Representatives and Minors
School privacy shifts the same way. Under the Family Educational Rights and Privacy Act, rights over education records transfer to you at 18 or when you enroll in a postsecondary institution at any age. Your college can’t share grades, discipline records, or enrollment status with a parent without your written consent, with one exception noted below for tax dependents.3Protecting Student Privacy. Eligible Student
Federal labor limits fall away. The Fair Labor Standards Act bars workers under 18 from hazardous jobs like mining, logging, roofing, and certain heavy machinery. At 18 those restrictions no longer apply.4eCFR. 29 CFR 570.120 – Eighteen-Year Minimum You can also vote, serve on a jury, and file lawsuits in your own name.
What You Are Now Responsible For
Selective Service
Almost all male U.S. citizens and male immigrants must register with the Selective Service System within 30 days of turning 18.5Selective Service System. Who Needs to Register Failing to register is a felony carrying a fine up to $250,000 and up to five years in prison. The practical penalties are more common: loss of eligibility for federal student aid, most federal jobs, federal job training, and, for immigrants, U.S. citizenship.6Selective Service System. Benefits and Penalties
Jury Duty
You become eligible for state and federal jury service at 18. Federal courts require jurors to be at least 18, a U.S. citizen, and a resident of the district for at least one year.7United States Courts. Juror Qualifications, Exemptions and Excuses Ignoring a summons can bring fines or contempt.
Adult Criminal Exposure
Before 18, most cases go through juvenile court, where the focus is rehabilitation. After 18, every charge is filed in adult criminal court. Drug possession, theft, or assault can lead to felony charges with prison time, fines, and a public record that follows you into job and housing applications. Arizona’s sentencing statute sets specific ranges by felony class.8Arizona Legislature. Arizona Revised Statutes Title 13, Section 13-702 – Sentencing
Civil Liability
You can be sued for damages you cause through negligence. Arizona uses pure comparative negligence, so even partial fault can mean paying your share of the loss.9Arizona Legislature. Arizona Revised Statutes Title 12, Section 12-2505 – Comparative Negligence If a creditor wins a judgment against you, Arizona law allows wage garnishment to collect unpaid debts.10Arizona Legislature. Arizona Revised Statutes Title 12, Section 12-1598.10
What Still Waits Until 21
Adulthood at 18 doesn’t unlock everything. A few important activities have a higher age floor:
- Alcohol purchase and consumption.
- Tobacco and vaping products. Federal law raised the minimum age to 21 in December 2019, and Arizona applies the same threshold.
- Gambling in Arizona, including casino gaming, lottery tickets, and pari-mutuel wagers.
- Buying a handgun from a federally licensed dealer. Long guns can be purchased at 18. Arizona doesn’t add a stricter state minimum.
- Credit cards. Under the Credit CARD Act of 2009, you generally can’t get a card before 21 unless you show independent income sufficient to cover payments or have a cosigner who is at least 21.11Federal Trade Commission. Credit Card Accountability Responsibility and Disclosure Act of 2009
Reaching Adulthood Before 18
Two paths let some minors take on adult status earlier. A minor who is at least 16 can petition the superior court for emancipation, which requires proof of financial self-sufficiency, stable housing, and the ability to manage their own affairs. The court weighs the minor’s understanding of the risks, employment history, school performance, any criminal record, and the parents’ views, and the minor carries the burden of clear and convincing evidence.12Arizona Legislature. Arizona Revised Statutes Title 12, Section 12-2451 – Petition for Emancipation Order13Arizona Legislature. Arizona Revised Statutes Title 12, Section 12-2453 – Factors; Best Interests of Minor; Burden of Proof An emancipation order grants the ability to contract, hold real estate, establish a residence, consent to medical care, enroll in school, borrow, and sue or be sued, and it ends parental support obligations and liability. It does not override age-based restrictions like voting, alcohol, or tobacco.14Arizona Legislature. Arizona Revised Statutes Title 12, Section 12-2454 – Effect of Emancipation
Arizona also permits marriage at 16 or 17 in limited circumstances. The minor must have either a court-ordered emancipation or the consent of a custodial parent or guardian, and the future spouse cannot be more than three years older. No one under 16 can marry in Arizona.15Arizona Legislature. Arizona Revised Statutes Title 25, Section 25-102 – Consent Required for Marriage of Minors
Things That Don’t Flip on Your 18th Birthday
Health Insurance
You don’t lose coverage under a parent’s plan at 18. The Affordable Care Act requires plans offering dependent coverage to keep you eligible until 26, whether you’re married, working, in school, or living at home.16U.S. Department of Labor. Young Adults and the Affordable Care Act: Protecting Young Adults and Eliminating Burdens on Businesses and Families FAQs What does change is privacy: providers can’t share your treatment details with a parent without a HIPAA authorization from you, though explanation of benefits statements sent to the policyholder can still reveal claim information.2HHS.gov. Personal Representatives and Minors
Tax Dependency
A parent can still claim you. Under IRS rules, a parent may claim an 18-year-old as a qualifying child if the child is under 19 at year end, lives with the parent more than half the year, doesn’t provide more than half of their own support, and doesn’t file a joint return except to claim a refund. Full-time students qualify until 24.17Internal Revenue Service. Dependents That tax status has a FERPA consequence: colleges can share records with a parent who claims you as a tax dependent, even without your consent.3Protecting Student Privacy. Eligible Student
Old Claims from Childhood
Arizona pauses the statute of limitations while you’re a minor. Under A.R.S. 12-502, time spent under 18 doesn’t count against a filing deadline, so the clock starts on your 18th birthday and you get the same period an adult would have.18Arizona Legislature. Arizona Revised Statutes Title 12, Section 12-502 – Effect of Minority or Insanity If you were injured as a child and didn’t pursue a claim, check the deadline before assuming it has passed.
When 18 Isn’t the Line
Minors Charged as Adults
Arizona doesn’t always wait for 18 in criminal cases. For first- and second-degree murder, armed robbery, and forcible sexual assault, the county attorney must charge 15-, 16-, and 17-year-olds as adults, with no judicial discretion. For juveniles as young as 14, the county attorney has discretion to file adult charges for other serious felonies, including class 1 and 2 felonies and dangerous offenses.19Arizona Legislature. Arizona Revised Statutes Title 13, Section 13-501 – Persons Under Eighteen Years of Age; Felony Charging A juvenile convicted in adult court faces adult sentencing and a public record.
Guardianship for Adults with Disabilities
If a young adult has an intellectual or developmental disability that prevents them from managing their own affairs, a court can appoint a legal guardian under A.R.S. 14-5304 after medical evaluations and a hearing on incapacity.20Arizona Legislature. Arizona Revised Statutes Title 14, Section 14-5304 Unlike parental authority, which ends automatically at 18, court-appointed guardianship continues until modified or terminated by the court. Families in this situation should start the process before the 18th birthday, because parental authority ends on that date regardless of the child’s capacity.