If you are receiving benefits on behalf of a child, there are important things you should know about his or her benefits.
When a child reaches age 18
A child's benefits stop with the month before the child reaches age 18, unless the child is disabled or is a full-time elementary or secondary school student and unmarried. About three months before the child's 18th birthday, you will get a letter explaining how benefits can continue. Social Security also will send the child a letter and a student form.