The basic rule: keep your car payment under 15 percent of your gross monthly income
Most lenders and financial advisors use a straightforward benchmark: your monthly car payment should not exceed 15 percent of your gross monthly income — that is, the money you earn before taxes and other deductions come out. This is not a law. It is a guideline based on what lenders have seen work for people over time.
If you earn $3,000 gross per month, 15 percent is $450. If you earn $5,000 gross per month, 15 percent is $750. The number changes with your income, not with what you want to spend.
Why this number? Because a car payment is not your only car cost. You also pay insurance, gas, maintenance, and registration. If your payment takes up too much of your income, you will not have money left for those other costs — or for rent, food, and emergencies.
Key Takeaways
- Your monthly car payment should stay under 15 percent of your gross monthly income — the money you earn before taxes.
- A car payment is only one cost; you also need to budget for insurance, gas, maintenance, and registration.
- If you cannot afford a payment at 15 percent or less, a less expensive car or a longer loan term may be the better choice.
- Some lenders will approve you for more than 15 percent, but that does not mean you can afford it.
- Your total monthly debt payments — car, credit cards, student loans, everything — should not exceed 36 to 43 percent of gross income.
Why lenders approve you for more than you should spend
A bank or dealership may tell you that you can afford a $600 or $700 monthly payment when your gross income is $3,000. They are using a different calculation than the 15 percent rule. They are looking at whether you can make that one payment, not whether you can afford a car and everything else at the same time.
Lenders often use what is called a debt-to-income ratio. They add up all your monthly debt payments — car loan, credit cards, student loans, mortgage or rent — and divide by your gross income. If that total is under 43 percent, many lenders will approve you. But that 43 percent includes your rent or mortgage, your utilities, your food, and everything else. A $600 car payment might fit the lender's math and still leave you short at the end of the month.
The 15 percent rule is stricter than what lenders require because it assumes you have other costs to pay. It is a safety margin.
How to calculate your 15 percent number
Write down your gross monthly income. This is the number on your pay stub before taxes, insurance premiums, or retirement contributions are taken out. If you are paid every two weeks, multiply your gross pay by 26 and divide by 12. If you are paid twice a month, multiply by 2. If your income varies — you work commission or gig work — use an average from the last three months.
Multiply that gross monthly income by 0.15. That is your 15 percent limit.
Example: You earn $4,200 gross per month. Multiply $4,200 by 0.15. Your answer is $630. Your car payment should not exceed $630 per month.
If you are looking at a car loan, you can work backward. If you know the interest rate and the loan term, a loan calculator will show you what price car that payment represents. If the payment is higher than your 15 percent number, the car is out of your budget.
What happens if you go over 15 percent
Going over 15 percent does not mean you will fail. It means you are taking a risk. The risk is that when an unexpected cost comes up — a medical bill, a job loss, a repair — you will not have the money to cover it and still make your car payment.
People who stretch their car budget often end up missing payments or going into credit card debt to cover other expenses. A missed car payment damages your credit score and can lead to the lender repossessing the car — taking it back because you did not pay.
If you are considering a payment above 15 percent, ask yourself: What happens if I lose my job for two months? What if my child needs dental work? What if my car needs a $1,500 repair? If you cannot answer "I have savings to cover that," the payment is too high.
Other costs that eat into your budget
Your car payment is only one piece. Before you commit to a payment amount, estimate your other monthly car costs.
Insurance is required by law in every state. The cost depends on the car, your age, your driving record, and where you live. A new car usually costs more to insure than an older one. Call an insurance company or use an online quote tool to find out what your specific car would cost to insure.
Gas depends on how much you drive and the car's fuel efficiency. If you drive 12,000 miles per year and gas costs $3.50 per gallon, a car that gets 25 miles per gallon costs about $168 per month in gas. A car that gets 15 miles per gallon costs about $280 per month.
Maintenance and repairs are unpredictable but real. A new car under warranty may have low costs for a few years. An older car may need $100 to $300 per month set aside for repairs. Budget something, even if you do not spend it every month.
Registration and taxes vary by state and car value. Some states charge $50 per year; others charge several hundred. Spread the annual cost across 12 months.
When 15 percent does not fit your situation
If 15 percent of your income is $200 per month but you need a car to get to work, you may not have many options. A $200 payment limits you to an older used car or a longer loan term on a newer car.
In that case, consider a longer loan. A five-year loan (60 months) has a lower monthly payment than a three-year loan (36 months) on the same car. The trade-off is that you pay more interest overall. But a payment you can actually afford is better than a payment that forces you to choose between the car and rent.
You can also look for a less expensive car. A car that costs $8,000 has a lower payment than one that costs $15,000, even at the same interest rate and loan term.
If you have a co-signer — someone who agrees to pay the loan if you cannot — some lenders will approve you for a higher payment. But this is risky for the co-signer. Do not ask someone to co-sign unless you are certain you can make every payment on time.
The total debt picture: car payment plus everything else
Your car payment does not exist in isolation. Lenders look at your total monthly debt — car, credit cards, student loans, mortgage or rent, medical debt, anything you owe money on — and compare it to your income.
Most lenders want your total debt payments to be no more than 36 to 43 percent of your gross monthly income. If you earn $4,000 gross per month, that means your total debt payments should not exceed $1,440 to $1,720.
If you already have $800 in student loan payments and $200 in credit card payments, you have $1,000 in debt already. That leaves $440 to $720 for a car payment, depending on which end of the range the lender uses. In this case, the 15 percent rule ($600) would be close to your actual limit.
Before you take on a car loan, add up all your current monthly debt payments. Subtract that from 43 percent of your gross income. The number left is the most a lender will likely approve you for — but it is not necessarily what you should spend.
Frequently Asked Questions
What if I earn irregular income or work gig jobs?
Use an average of your last three months of income. If your income is growing or shrinking, use the lower number to be safe. Some lenders will ask for tax returns or bank statements to verify your average income before they approve you.
Does the 15 percent rule include insurance and gas?
No. The 15 percent rule is just the loan payment itself. You budget for insurance, gas, and maintenance separately. That is why 15 percent is a limit, not a target — you want room in your budget for those other costs.
Can I afford a car payment if I have no other debt?
Yes, you have more room. If you have no credit cards, student loans, or other debt, you can go closer to 20 percent of your gross income on a car payment and still stay under the 43 percent total debt limit. But you still need to budget for insurance, gas, and maintenance.
What if I can only afford a payment that is 20 percent of my income?
You can take that payment, but you are taking on more risk. If you lose income or face an unexpected expense, you may struggle to make the payment. Consider whether you can delay buying a car, save for a larger down payment to lower the monthly payment, or buy a less expensive car.
Should I use gross or net income for this calculation?
Always use gross income — the money before taxes come out. Lenders use gross income because it is the same number on your pay stub and tax return. Using net income would make your budget look better than it actually is.