How Much Should You Put Down on a Car?

Updated September 2026 · 4 min read

A good target is 20% down on a new car and at least 10% on a used car. The point of a down payment is not just a smaller monthly bill - it is to keep the loan balance below the car's value so you are never upside-down.

Why 20%?

New cars tend to lose about 20% of their value in the first year. If you finance the whole price, you owe more than the car is worth the moment you drive off, and the gap widens for a year or two. A 20% down payment roughly offsets that first-year drop.

What it does to your payment

Take a $30,000 car at 7% for 60 months:

• Nothing down: about $594 a month, and about $5,600 in total interest.
• 20% down ($6,000): about $475 a month, and about $4,500 in interest.

The $6,000 down saves roughly $120 a month and over $1,000 of interest, and it removes the negative-equity risk.

If you cannot put 20% down

• Choose a shorter term so the balance falls faster than depreciation.
• Buy a less expensive car - the down payment problem is really a price problem.
• Add gap insurance as a stopgap if you are financing most of the price.

A trade-in counts as a down payment. So does cash you add at signing. Run the numbers with the auto loan calculator and see the true cost with the ownership calculator.

What actually counts as a down payment

Anything applied to the price before financing reduces the loan: cash, a trade-in, and a manufacturer rebate you direct at the price rather than taking as cash back. A trade-in is the most common, and its value should be negotiated separately from the new car's price so neither number hides the other. If you are upside-down on the trade, the negative equity is added back to the loan, which can wipe out your down payment entirely and leave you borrowing more than the car is worth.

Frequently asked questions

Is 0% down ever a good idea?

Only if the rate is 0% or you are keeping the cash as an emergency buffer. Otherwise it leaves you upside-down immediately.

How much should I put down on a used car?

At least 10%, ideally 20%. Used cars depreciate more slowly, so a smaller down payment is less risky than on a new car.