What You Can Legally Do When You're 18

"Coming of age" is more than a concept out of historical novels. All people pass from childhood into the world of adults as they attain the age of majority. For most purposes, that happens at the age of 18. So what can you do when you finally get to be 18 years old? Many doors open to you on that momentous day, and a few doors close.

The age of majority is the birthday that ushers you into adulthood. Exactly when it came to be 18 rather than 21 is a good question without a clear answer, but it may have been when the 26th Amendment to the U.S. Constitution was passed giving the right to vote to 18 year olds. That amendment says: "The right of citizens of the United States, who are eighteen years of age or older, to vote shall not be denied or abridged by the United States or by any State on account of age.” It was passed during the time of the Vietnam War when it seemed unfair to many to force young men to fight in the military when they couldn’t even vote for or against their elected leaders.

The 26th Amendment did not mandate that all states make 18 the age of majority for purposes other than voting. But over time, most of them did. Today, all but three states have laws setting 18 as the age of majority, when a young person assumes the rights and responsibilities of an adult. Alabama and Nebraska make 19 the age of majority, while in Mississippi, you have to wait until you turn 21 years old.

While there are exceptions, most states allow anyone who reaches the age of majority to have all of the rights of an adult, other than the right to drink alcohol. One primary legal right is the right to enter into binding contracts. Generally, a minor cannot be bound to a contract he signed, making merchants and business people unwilling to contract with minors.

What other things can you do when you're 18? You can do on your own all of the things you needed parental consent to do when you were a minor. This includes marrying, moving out of the house, getting a driver's license, getting a passport and writing a will. You can take care of your own finances and medical decisions without consulting, and certainly without deferring, to your parents.

You may be initially thrilled to enter the world of adults. But it comes with responsibilities. The right to enter into a binding contract means that someone can sue you if you fail to live up to your written promises. Any parental support after the age of majority is usually voluntary, and child support payments for your benefit usually cease. You are responsible for your own debts and for supporting yourself.