Legal Age Requirements for Vehicle Purchases

In nearly every U.S. state, the legal age to buy a car and sign a binding purchase contract is 18 years old. That’s because car purchases involve legally enforceable agreements, and minors (anyone under 18) generally cannot be held to the terms of a contract in civil court. If a person under 18 signs, they usually retain the legal right to cancel it at any time, making it too risky for dealerships and lenders to approve.

This legal threshold applies not just to financing agreements but also to title and registration paperwork. Even if you pay in cash, most dealerships will not complete the sale under a minor’s name alone, as they may face legal challenges if the contract is later voided.

Some states may allow minors to co-own vehicles or have their names listed on a title alongside an adult, but that does not give them the ability to sign contracts independently. For anyone under 18 who wants to buy their first vehicle, understanding this legal barrier is the first step to planning.

Options for Younger Buyers

While you can’t legally purchase a vehicle outright under 18, there are ways to make ownership possible with the help of an adult. The most common method is having a parent or guardian co-sign the purchase or loan agreement.

A co-signer is an individual over 18 who agrees to be legally responsible for the debt if you fail to make the payments. They also help reassure the lender that payments will be made on time. This option is often used by 16–17-year-olds with part-time jobs who are ready to start building their financial independence.

Another route is for the adult to buy the car in their name and allow the minor to be the primary driver. While the minor won’t legally own the vehicle until turning 18, they can still use and maintain it while building driving experience. When they reach legal age, ownership can be transferred to their name.

Parents should keep in mind that co-signing carries risk: any missed or late payments will appear on the co-signer’s credit report and can impact their ability to borrow in the future. Because of this, it’s wise to ensure the young buyer has a steady income or savings in place before signing.

Financing Considerations for Young Buyers

Even for adults, financing a car involves meeting lender requirements, including income, employment history, and a satisfactory credit score. This can be challenging for younger buyers who haven’t yet built a credit history.

Lenders look for indicators that show you can handle debt responsibly—typically, a steady income, a low debt-to-income ratio, and a history of on-time payments. If you’re starting and don’t have this record yet, approval will be more difficult without a co-signer.

Here are a few ways younger buyers can improve their chances:

• Save for a larger down payment. A higher down payment reduces the loan amount and reassures lenders.
• Build starter credit. Using a secured credit card or becoming an authorized user on a parent’s card can establish a credit history.
• Consider paying with cash. This avoids the need for financing and may simplify the transaction if a co-signer is involved.

Keep in mind that while a co-signer helps secure the loan, the primary borrower (the younger buyer) is still expected to make the monthly payments. Missing payments can damage both credit profiles.

Insurance and Registration Rules

Owning a car goes beyond buying it—you’ll also need to register it and carry insurance before driving it off the lot. This can be another hurdle for young buyers.

Most states allow minors to be listed as the primary driver on an insurance policy. Still, an adult usually must be the policyholder if the vehicle is not legally in the minor’s name. Insurance rates are often much higher for drivers under 25, especially teens, due to higher statistical risk. Expect to pay significantly more in premiums than older drivers, even with a clean record.

Registration is also tied to ownership. The person who owns the car (or the co-signer if the buyer is a minor) must be listed on the title and registration. Some states allow joint ownership between a parent and child to reflect who drives it most.

It’s a good idea to request insurance quotes early so you can estimate the full monthly cost of ownership—including car payments, gas, and maintenance.

Preparing to Buy Your First Car

Buying your first car is a milestone, but it can also be overwhelming if you’re not prepared. Teen and young adult buyers should approach it like any major purchase: with planning, research, and a clear budget.

Start by identifying your needs: Will you be commuting daily, driving long distances, or mainly using it for local errands? Consider factors like fuel efficiency, reliability, safety ratings, and cargo space. Once you have a list of potential vehicles, compare prices from local dealerships and private sellers.

It’s also essential to calculate total ownership costs, not just the sticker price. Add up estimated monthly loan payments, insurance premiums, gas, regular maintenance, and registration fees. This will give you a realistic view of what you can afford.

If you’re unsure how to structure this process, our guide on tips for first-time car buyers can help you stay organized and avoid common mistakes. Building this foundation early ensures you make a decision that fits both your lifestyle and your budget.

What Young Car Buyers Should Know Before Purchasing

You must be 18 to sign a vehicle purchase contract on your own legally. If you’re under 18, you’ll need a co-signer to handle the legal and financial responsibilities until you reach adulthood. Beyond simply meeting the age requirement, it’s important to understand how a car purchase affects your long-term financial profile. Taking on an auto loan will establish a payment history that can influence your ability to qualify for credit cards, apartments, or other loans later.

You should also be prepared for the extra responsibilities that come with ownership, such as scheduling regular maintenance and keeping accurate records. Knowing how to evaluate a car’s reliability—by reading safety ratings, checking recall histories, and looking for signs of wear—can prevent unexpected repair costs. It’s equally valuable to practice comparing prices across multiple dealerships to recognize fair market values and avoid overpaying.

Spending time learning how interest rates, loan terms, and trade-in values work will give you an edge when negotiating. Consider creating a basic monthly budget that includes gas, registration renewals, and repair savings so you can see how much of your income is available for a payment. Developing these habits early will help you become a more confident buyer and reduce stress when you finally sit down to sign the paperwork.