The Big Questions

Turning 18: a checklist for the years before and after

At 18 a young adult with IDD becomes a legal adult. School rights move to them, benefits rules change, and wait lists matter more. Start early.

What changes at 18

In most states a person becomes a legal adult at 18 (19 in Alabama and Nebraska, 21 in Mississippi). From that day they make their own decisions about health care, money, school, and where they live, unless a court says otherwise.

  • School rights move to the student. Under IDEA, the school must tell the family and student at least one year before the age of majority that the rights will transfer.
  • Doctors and schools stop sharing information with parents unless the young adult says yes in writing.
  • SSI looks only at the young adult's own income and savings, not the parents'. Many young adults qualify for the first time at 18.

Ages 14 to 16

  • Get on your state's Medicaid waiver wait list if you have not already. Some lists are many years long. See your state's programs.
  • Make sure the IEP has a transition plan with real goals for work, learning, and living.
  • Ask the state vocational rehabilitation agency about Pre-Employment Transition Services.
  • Start practicing decisions: choosing activities, making appointments, handling a little money.
  • Open an ABLE account if saving money matters. ABLE accounts.

Ages 16 to 17

  • Talk together about what help with decisions will look like after 18. Learn the options from least to most restrictive in Guardianship and its alternatives.
  • If you are thinking about guardianship, start about six months before 18. Courts take time.
  • Plan the move from a pediatrician to adult doctors. Ask the current doctor for names.
  • Get a state ID card. Make copies of the Social Security card and birth certificate.
  • Write down who the young adult wants as their support people.

At 18

  • Apply for SSI the month of the 18th birthday. Call Social Security at 1-800-772-1213 or start at ssa.gov. SSI in plain language.
  • If the young adult already got SSI as a child, Social Security will review the case using adult rules. Answer every letter on time.
  • Sign release forms (HIPAA forms and FERPA forms) so the young adult can choose to share health and school records with family.
  • Sign supported decision-making agreements or powers of attorney, if chosen.
  • Register to vote. Disability does not take away the right to vote in most cases.
  • Most young men age 18 to 25 must register with Selective Service, including many with disabilities. Some are exempt. Check sss.gov.
  • Ask about Medicaid in your own name, which often comes with SSI.

18 to 22

  • Stay in school services until the student earns a regular diploma or ages out, if that helps.
  • Look at jobs, job training, and supported employment. Search Work and Jobs.
  • Look at day programs, college programs, and places to live. Independent living.
  • Keep the waiver wait list current. Update your address and phone if they change.

Last reviewed: October 2026. Laws, dollar amounts, and program rules change. Check with the agency named on this page before you make a decision.