Luis Puente

Luis Puente

Financial Education

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February 18, 2019

Do you use the 20/4/10 rule?

Do you use the 20/4/10 rule?

If you’re in the market for a new car, you may already be aware that the average cost of a new car is about $35,000.

This pricetag has been increasing steadily in recent decades.[i] As a result, there are some “new” loan options that allow you to spread out your payments for up to 7 years.

Having a longer time to pay back your auto loan may seem like a great idea – stretching out the loan period may lower the payments month-to-month, and help squeeze a new car purchase into your family budget without too much financial juggling.

Reality check
One thing to keep in mind is that cars depreciate faster than you might imagine. Within the first 30 days, your new car’s value will have dropped by 10%. A year later, the car will have lost 20% of its value. Fast forward to 5 years after your purchase and your car is now worth less than 40% of its initial cost.[ii]

If you go with a longer loan term, it will take that much more time to build equity in the vehicle. A forced sale due to an emergency or an accident that totals your vehicle may mean you’ll still owe money on a car you no longer have. (This is what’s meant by being “upside down” in a loan: you owe more than the item is worth.)

If you’re not sure what to do, consider the 20/4/10 rule.

1. Try to put down 20% or more. Whether using cash or a trade-in that has equity, put down at least 20% of the new vehicle’s purchase price. This builds instant equity and may help you stay ahead of depreciation. Also add the cost for tax and tags to your down payment. You won’t want to pay interest on these expenses.

2. Take a loan of no longer than 4 years. Longer term loans may lower the monthly payments, but feeling like you need a loan term of more than 4 years may be a red flag that you’re buying more car than you can comfortably afford. With a shorter term loan, you may get a better interest rate and pay less interest overall because of the shorter term. This may make quite a difference in savings for you.

3. Commit no more than 10% of your gross annual income to primary car expenses. Your primary expenses would include the car payment (principal and interest), as well as your insurance payment. Other expenses, like fuel and maintenance, aren’t considered in this figure. The 10% part of the 20/4/10 rule may be the most difficult part to follow for many households considering purchasing a new car. Feeling pinched if you go with a new car could suggest that a reliable used car may be a better financial fit.

Cars are often symbolic of freedom, so it’s no wonder that we sometimes get emotional about car-buying decisions. It’s often best – as with any major purchase – to take a step back and look at the numbers and how they would affect your overall financial strategy, budget, emergency fund, etc. The money you save if you need to go with a used car could be used to build your savings or treat your family to something special now and then – and you’ll enjoy the real freedom of not being a slave to your monthly auto payment.

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This article is for informational purposes only and is not intended to promote any certain products, plans, or strategies that may be available to you. Before taking out any loan, seek the advice of a financial professional, accountant, and/or tax expert to discuss your options.

[i] https://www.prnewswire.com/news-releases/average-new-car-prices-jump-2-percent-for-march-2018-on-suv-sales-strength-according-to-kelley-blue-book-300623110.html
[ii] https://www.carfax.com/blog/car-depreciation