How is a car loan monthly payment calculated?

Car loan payments use the standard amortization formula: Payment = P × [r(1+r)ⁿ] / [(1+r)ⁿ − 1], where P is the financed amount (price + tax + fees − down payment − trade-in + negative equity − rebates), r is the monthly interest rate (APR ÷ 12), and n is the total number of payments.

Does my trade-in reduce sales tax?

In most US states (like Texas, Florida, and New York), yes—you only pay sales tax on the difference between the new car price and your trade-in value. However, states like California, Virginia, Hawaii, and DC tax the full purchase price regardless of trade-in. Our calculator auto-applies the correct rule based on your selected state.

What is the OBBBA auto loan interest deduction?

The One Big Beautiful Bill Act (OBBBA) is a federal tax law that allows eligible buyers to deduct up to $10,000 per year in auto loan interest on their federal taxes for years 2025–2028. To qualify, you must finance a new, US-assembled vehicle for personal use. It is an above-the-line deduction, so you can claim it even if you take the standard deduction.

Is the dealer's interest rate negotiable?

Yes. Dealerships usually present you with a 'sell rate,' which includes a hidden markup of 1% to 2.5% above the 'buy rate' you actually qualified for. To protect yourself, always get pre-approved from a credit union or bank before visiting the dealership, and ask the finance manager directly if they are offering the buy rate.

Should I get a 72 or 84 month car loan?

Almost never. While 84-month loans lower your monthly payment, they trap you in negative equity (being underwater) for years because cars depreciate faster than you pay down the principal on an 84-month schedule. Financial experts strongly recommend financing new cars for 60 months max, and used cars for 48 months max.

Can I refinance my car loan?

Yes, you can refinance if you meet three conditions: your credit score has improved by 40+ points since you bought the car (or interest rates have dropped significantly), you have at least 24 months left on the loan, and you do not owe more than the car is worth (no negative equity). Always make sure your new loan term matches your remaining months so you don't extend your debt.

Do I need GAP insurance?

You need GAP insurance if you put little to no money down, took out a long-term loan (60+ months), or are leasing. However, do not buy it from the dealership, where it costs $500–$1,000+. Call your primary auto insurance provider, who can usually add it to your policy for just $5 to $15 a month.

How do tariffs affect car prices in 2026?

The 25% import tariff on vehicles and auto parts implemented in early 2025 has driven new vehicle prices up by $3,000 to $10,000 across the industry. Even domestically assembled vehicles are affected because they rely on imported electronics and components. This means you are borrowing more money and paying more interest than buyers did a few years ago.

Should I pay cash or finance a car?

Historically, paying cash saves you from paying interest. However, with the new OBBBA auto loan interest tax deduction (2025-2028), the math can change. If your vehicle qualifies for the deduction, and you can invest your cash at a higher return rate than your loan's APR, financing might actually be the smarter financial move.

What credit score do I need for the best car loan rate?

To get the absolute lowest 'Super Prime' rates (averaging ~4.66% on new cars in early 2026), you typically need a credit score of 781 or higher. 'Prime' borrowers (661-780) still get competitive rates averaging around 6.27%. If your score is below 600, your interest rate can easily exceed 13%, costing thousands more over the life of the loan.

Auto Loan Calculator

Compare payments, taxes, trade‑in equity, and find the true cost of your vehicle

Vehicle & Purchase

Vehicle Type

Vehicle Price$35,000

Down Payment$5,000

I have a trade-in

Taxes & Fees

Region

State

Sales Tax RateTax: $2,188

Finance sales tax into loan

Registration Fee

Dealer / Doc Fee

Rebates / Incentives

Financing

Credit Score

Interest Rate (APR)6.27%

Loan Term60 months (5.0 yrs)

Payment Frequency

48-month term saves $1,103

48 months instead of 60 saves $1,103 in interest, but payment rises by $133.59.

72-month term adds $1,124

Extending to 72 months lowers payment by $88.77 but costs $1,124 more in total interest.

Cost Breakdown

86%

Principal

Principal (86%)

Interest (14%)

Loan Summary

Payment$626.32

Loan Amount$32,188

Total Interest$5,392

Total of 60 Payments$37,579

Loan Balance Over Time

Monthly Payment

$626.32

Loan Amount$32,188

Down Payment$5,000

Sales Tax$2,188

Total Interest$5,392

Total Repayment$37,579

Total Cost of Ownership

$42,579

loan + down + financed tax + fees

Loan Overview

APR6.27%

Credit TierPrime

Loan Term60 months (5.0 yrs)

Payoff DateJul 2031

Interest-to-Principal16.8%

Year 1 Interest26% of payments

Total Cost$42,579

PrincipalInterest

$32,188$5,392

Secured Loan

Auto loans are secured by the vehicle. If you default, the lender can repossess the car.

How to Use This Auto Loan Calculator

Estimate your monthly car payment, total cost of ownership, and explore term scenarios in under a minute. This calculator is built for US and Canadian buyers who want to compare rates, fees, taxes, and trade-in options before visiting the dealership.

Enter the vehicle price or your budget
Start with the MSRP or negotiated price of the car you want. Switch to Affordability mode if you want to find the most car you can buy for a target monthly payment.
Add your down payment and trade-in
Enter your cash down payment. If you have a trade-in, toggle it on and enter the trade-in value and any remaining loan balance — the calculator handles negative equity automatically.
Set your state or province for sales tax
Select your US state or Canadian province. The calculator auto-fills the correct sales tax rate including trade-in deduction rules. You can always override for local taxes.
Choose your credit tier and loan term
Select your credit score range to auto-fill an APR based on real market data (Experian Q1 2026). Then choose a loan term — use the preset buttons to quickly compare 24 to 84 months.
Review results and explore insights
See your monthly payment, total interest, total cost of ownership, and amortization schedule. The smart insights show how shorter terms, biweekly payments, or negative equity affect your costs.

The Dealer Rate Markup Nobody Tells You About

When you finance a car at the dealership, the interest rate you are offered is rarely the lowest rate you actually qualified for. In most cases, the dealer adds a "markup" to the bank's base rate—and keeps the difference as profit.

Here's the thing: lenders give dealerships a "buy rate" (the actual interest rate based on your credit score). The dealership then presents you with a "sell rate" that is typically 1% to 2.5% higher. This practice is so widespread that in 2025 alone, the Consumer Financial Protection Bureau (CFPB) received over 28,500 complaints about auto loans, many concerning hidden markups and pricing disparities.

The Real Dollar Impact

If you finance a $35,000 car over 60 months, a hidden 2% dealer markup doesn't just sound like a slightly higher rate—it adds approximately $1,900 in extra interest over the life of the loan. That's $1,900 of pure dealer profit that comes directly out of your pocket.

How to Protect Yourself

In early 2026, the CFPB finalized a new disclosure rule requiring more transparency around these buy rates, but the best protection is still proactive strategy.

Get pre-approved: The single most powerful move you can make is getting pre-approved for an auto loan from a credit union or bank before you walk into a dealership. This gives you a firm benchmark.
Ask the direct question: When sitting with the finance manager, ask them directly: "Is this the buy rate, or your markup rate?"
Know your baseline: Use our calculator's Experian-based APR data above to see the average rate for your credit tier (e.g., 6.27% for Prime borrowers in Q1 2026) before you start negotiating.

The 2026 Auto Loan Interest Deduction You're Probably Missing

Did you know you can now deduct your car loan interest from your federal taxes? Most people don't, because it's brand new. The One Big Beautiful Bill Act (OBBBA), signed in July 2025, created a powerful new tax deduction that allows eligible buyers to deduct up to $10,000 per year in auto loan interest for tax years 2025 through 2028.

Who Qualifies?

This isn't for everyone. The IRS (Publication 6126) has strict rules on what qualifies for the deduction:

New Vehicles Only: Used cars and leases do not qualify.
US Final Assembly: The vehicle must have undergone final assembly in the United States. (You can check any vehicle's status using the NHTSA VIN Decoder).
Loan Timing: Your loan must have been originated on or after January 1, 2025.
Personal Use: The vehicle must be for personal, non-business use.
Income Limits: The deduction phases out if your Modified Adjusted Gross Income (MAGI) is over $100,000 for single filers or $200,000 for married couples filing jointly.

The Best Part: Above-The-Line

This is an "above-the-line" deduction. That means you can claim it even if you take the standard deduction.

The Math: If you finance $40,000 at 6.27% for 60 months, your Year 1 interest is roughly $2,400. That's $2,400 subtracted directly from your taxable income. If you're in the 22% tax bracket, that saves you $528 on your tax bill just in the first year.

Tip: Run your numbers in our calculator above, then check the "Yearly Summary" in the amortization schedule. The total interest paid in Year 1 is exactly what you could potentially deduct if your vehicle meets the OBBBA criteria.

The 84-Month Loan Trap — What Your Payment Hides

Car prices are high (averaging $43,925 for a new vehicle in Q1 2026 according to Experian), and dealers know that high prices scare away buyers. Their favorite solution? Stretching out the loan term to 72 or even 84 months to make the monthly payment look affordable.

As of Q2 2026, J.D. Power reports that 23.9% of all new vehicle loans are for 84 months or longer—an all-time high. But what they don't show you is the depreciation crossover math, which turns these long loans into financial traps.

The 60-Month Reality

With a standard 60-month loan, you pay down the principal fast enough to keep up with the car's depreciation. By month 18 to 24, your car is typically worth more than you owe on it. You have positive equity.

The 84-Month Trap

A new car loses 20–30% of its value in Year 1. But on an 84-month loan with a minimal down payment, you've only paid off about 14% of the principal by month 12. You are deeply underwater, and you might not break even until month 42 to 48.

The Dollar Difference

Let's say you finance a $45,000 vehicle with $3,000 down at 6.27% APR.

At 60 months: Your payment is $825/month. You are above water by month 20.
At 84 months: Your payment drops to $623/month. It feels cheaper! But you stay underwater for nearly four years, and you pay ~$3,800 more in total interest.

We strongly recommend keeping new car loans to 60 months maximum, and used car loans to 48 months. If you have to stretch the loan to 84 months just to afford the monthly payment, you are buying too much car.

Use the "Term Comparison" insight in our calculator to see the exact dollar difference for your specific numbers.

Negative Equity Is an Epidemic — Here's How to Escape

In Q1 2026, 30.9% of trade-ins toward new vehicles carried negative equity, with buyers being upside down by an average of $7,183 (Edmunds data). Being "upside down" means you owe more on your car loan than the car is currently worth. It is a financial epidemic, driven by high interest rates, inflated prices, and those 84-month loans we warned about above.

The Rolling Debt Death Spiral

The most dangerous mistake you can make is trading in a car while you have negative equity and letting the dealer "roll it into the new loan."

If you trade in a car that is $8,000 underwater, that $8,000 doesn't disappear. It gets added to the principal of your new loan. If you buy a $40,000 car, you now have a $48,000 loan. You are instantly underwater on the new car on day one, and you are paying fresh interest on the old car's debt. At 6.27% over 60 months, rolling over $7,183 in negative equity actually adds over $8,500 to your total cost.

The 3 Ways Out

If you are currently underwater, there is no magic solution. The consensus among financial experts (and communities like r/personalfinance) points to three painful but necessary paths:

Drive it out (The Best Option): Keep the car. Stop the cycle of trading in. Make aggressive extra payments directly toward the principal every month until the balance drops below the car's market value.
Sell privately + cover the gap: Dealerships offer wholesale value for trade-ins. Selling your car privately often yields $2,000 to $5,000 more. If you sell it privately and bring cash to cover the remaining gap, you can clear the debt without rolling it over.
Cancel add-ons: Did you buy an extended warranty, maintenance package, or GAP insurance when you bought the car? You can often cancel these at any time for a prorated refund, which is sent directly to your lender and applied to your principal.

Our calculator handles negative equity automatically. Toggle "Trade-In" on, enter your trade-in value and the remaining loan payoff amount, and see exactly how it spikes your new monthly payment and total interest.

GAP Insurance — Don't Buy It from the Dealer

Guaranteed Asset Protection (GAP) insurance covers the difference between what your car is worth and what you owe on your loan if the vehicle is totaled or stolen. If you owe $30,000 but the insurance company determines the car is only worth $22,000, GAP insurance pays that $8,000 shortfall so you don't have to write a check for a car that no longer exists.

It is a genuinely important safety net—especially if you put little money down or took a long-term loan. But you should almost never buy it from the dealership.

The Dealer Markup

Dealerships typically charge a flat fee of $500 to $1,000+ for GAP insurance. Worse, this cost is usually rolled into your auto loan, meaning you are paying interest on the insurance premium for the next 5 to 7 years. Financing an $800 GAP policy at 6.27% for 60 months costs you ~$933 total.

The Third-Party Solution

Most major auto insurance companies offer GAP coverage as a simple add-on to your collision policy for roughly $5 to $15 per month ($60–$180/year). You pay as you go, without financing charges.

The Secret to Canceling GAP

One of the biggest mistakes buyers make is keeping GAP insurance for the entire life of the loan. You only need GAP insurance while you are underwater (negative equity).

Check our calculator's Amortization Schedule. Look at the balance column over time. Once your remaining loan balance drops below your car's current Kelley Blue Book or Edmunds value, you no longer need GAP coverage. Call your insurer and cancel it. If you bought the overpriced dealer policy, contact the dealership to cancel it and request a prorated refund applied to your loan principal.

The Tariff Tax You're Already Paying

If you are using our Affordability Mode to see how much car you can buy, you need to understand why the numbers look so much worse than they did a few years ago. In April and May of 2025, the US government implemented a 25% tariff on imported vehicles and auto parts.

The Immediate Impact

Industry analysts at Cox Automotive and TrueCar report that these tariffs have driven new vehicle prices up by 10% to 15% across the board. That translates to an average sticker price increase of $3,000 to $10,000 per vehicle.

And if you think buying a "domestic" brand shields you from this, think again. A vehicle assembled in Michigan or Ohio still relies on thousands of imported components—from transmissions to semiconductor chips—all of which are subject to the 25% parts tariff. Manufacturers have passed these supply chain costs directly to the consumer.

How It Affects Your Loan Math

You aren't just paying a higher price for the car; you're paying years of interest on that inflated price. Financing a $5,000 tariff-driven price hike at a 6.27% APR over 60 months adds about $830 in extra interest on top of the principal. The used car market isn't a safe haven either—as new cars become unaffordable, demand shifts to used cars, driving those prices up in tandem.

Strategy: This is the new reality of the auto market. When shopping, check the vehicle's window sticker for its domestic parts content (mandated by the American Automobile Labeling Act). Vehicles with high US/Canadian parts content have experienced slightly smaller price hikes. Most importantly, use our Affordability Mode to set a hard limit based on your monthly budget, and do not let a dealer stretch your loan to 84 months just to hide the tariff premium.

When (and When Not) to Refinance Your Car Loan

"Should I refinance my car loan?" is one of the most common questions buyers ask after driving off the lot. Most financial advice gives a frustrating "it depends." We recommend a concrete framework. Refinancing makes mathematical sense only if all three of the following conditions are true:

Your credit score has significantly improved (or you were scammed by a markup). If your credit score jumped 40+ points since you bought the car, or you realized the dealer padded your rate with a 2% markup, you are a prime candidate for a lower APR.
You have 24+ months remaining. Refinancing always comes with minor fees (usually $0 to $75 for title transfer and origination). Because auto loans are front-loaded (you pay most of the interest in the first half of the loan), refinancing when you only have 12 months left rarely saves enough to justify the hassle.
You are not underwater. Most reputable lenders will not approve a refinance if your Loan-to-Value (LTV) ratio is over 125%. If you owe $30,000 on a car worth $20,000, you will likely be denied until you pay down the principal.

The Danger of the Amortization Reset

What most people miss about refinancing is that it resets your loan clock. If you are 24 months into a 60-month loan, and you refinance into a new 60-month loan to lower your payment, you just extended your total time in debt to 84 months. You will likely pay more total interest, even with a lower rate. Always insist that your new loan matches your remaining term.

The 6-Month Rule

Wait at least 6 months after buying the car before you try to refinance. This gives your credit score time to bounce back from the initial hard inquiry and establishes a history of on-time payments. Start your search at local credit unions, which consistently offer the lowest auto loan refinance rates in the market.

Try the math right now: Take your current loan balance and enter it into our calculator above as the "Vehicle Price" with $0 down. Enter your potential new interest rate and the remaining months on your current loan. Compare the total interest to what your current bank statement says you'll owe.

Want a dedicated tool? Use our Refinance Calculator to run the exact break-even math.

Credit Union vs. Bank vs. Dealer — Where to Get Your Loan

Walking into a dealership without financing secured is the fastest way to overpay for a car. Your financing strategy is just as important as negotiating the price of the vehicle itself.

Factor	Credit Union	Bank	Dealership
Typical APR	Lowest (Often 0.5–1.5% below banks)	Mid-range	Highest (Includes markup profit)
Pre-Approval	Yes, fast and easy	Yes	Not standard
Negotiation Power	High — You are a "cash buyer"	High	None — Dealer controls terms

The 0% APR Trap

Manufacturer 0% financing sounds unbeatable, but it often comes with a severe catch. You usually have to choose between the 0% financing or massive cash rebates on the purchase price. Frequently, taking the $3,000 cash rebate and financing at a credit union's 5.5% APR results in a lower total cost than taking the 0% APR with no rebate. Furthermore, 0% loans are often restricted to 36- or 48-month terms, driving the monthly payment incredibly high.

Beware the "Four-Square" Tactic

Dealers often use a "four-square" worksheet to juggle the purchase price, your trade-in value, your down payment, and your monthly payment all at the same time. This is designed to confuse you. If you complain about the monthly payment, they just extend the loan term without lowering the car's price.

The Playbook: Get pre-approved at a credit union first. Walk into the dealer and negotiate only the out-the-door price of the car. Do not discuss monthly payments. Do not discuss your trade-in until the price of the new car is locked. Once the price is set, let the dealer try to beat your credit union's pre-approved rate. You win either way.

Worried about multiple credit hits? The FICO scoring model treats all auto loan inquiries made within a 14-to-45-day window as a single hard pull. You can and should shop aggressively for the best rate without tanking your credit score.