Vehicle depreciation is calculated two different ways depending on who’s doing the math. The IRS uses a set of fixed percentage tables (the Modified Accelerated Cost Recovery System, or MACRS) capped by annual dollar limits under Section 280F, so a business owner writes off a work vehicle over roughly six tax years subject to a first-year ceiling of $20,300 for passenger cars placed in service in 2026. Insurance companies calculate depreciation as the gap between what you paid and what a comparable used vehicle sells for today, and that number decides your payout when a car is totaled. Both calculations start from the same idea: cars lose value over time. They diverge on method, purpose, and result.
What Cars Actually Lose Each Year
Bureau of Labor Statistics figures show a new car loses roughly 24% of its value in the first year alone. The decline continues at about 11% in year two, another 11% in year three, and around 14% in year four. By the end of five years the average car has shed close to 74% of its original price.1Bureau of Labor Statistics. Annual Depreciation Rates by Automobile Age
Those are averages. Luxury brands and high-volume models depreciate faster; trucks, certain SUVs, and vehicles with strong resale reputations hold value better. Mileage, condition, accident history, and paint color all push the number up or down. A $40,000 car can be worth less than $11,000 five years later, and both the IRS and your insurer build formulas that assume this kind of decline.
The Straight-Line Method
The simplest calculation is straight-line depreciation. Take the vehicle’s original cost, subtract the salvage value you expect at the end of its useful life, and divide by the number of years you plan to use it. That gives you a flat annual amount.
A $40,000 delivery van you expect to be worth $10,000 after six years has a depreciable base of $30,000, or $5,000 per year. Book value drops by the same amount every year until it hits the $10,000 floor. This method assumes uniform wear regardless of how the vehicle is driven, which makes it easy to project but not what the IRS actually requires for business vehicles.
MACRS: The IRS Method for Business Vehicles
Business vehicles are depreciated on a tax return using MACRS, which front-loads deductions into the early years.2Office of the Law Revision Counsel. 26 USC 168 – Accelerated Cost Recovery System Passenger cars and light trucks are five-year property, but the cost basis is recovered over six tax years because of the half-year convention (which treats the vehicle as placed in service at the midpoint of year one).
The 200% declining balance percentages for five-year property with the half-year convention are:3Internal Revenue Service. Publication 946 – How To Depreciate Property
- Year 1: 20.00%
- Year 2: 32.00%
- Year 3: 19.20%
- Year 4: 11.52%
- Year 5: 11.52%
- Year 6: 5.76%
Each percentage applies to the original cost basis, not a declining balance, which keeps the math simple. On a $50,000 vehicle, year one is $10,000, year two is $16,000, and so on. Deductions are reported on Form 4562. In practice, though, most passenger vehicles never actually follow this schedule, because separate dollar caps override the percentages.
Section 280F Caps for 2026
Section 280F sets hard annual ceilings on depreciation for any passenger automobile weighing 6,000 pounds or less, regardless of what MACRS would otherwise allow.4Office of the Law Revision Counsel. 26 U.S. Code 280F – Limitation on Depreciation for Luxury Automobiles The caps are indexed for inflation. Rev. Proc. 2026-15 sets these limits for vehicles placed in service in 2026:5Internal Revenue Service. Rev. Proc. 2026-15
With bonus depreciation applied:
- Year 1: $20,300
- Year 2: $19,800
- Year 3: $11,900
- Each succeeding year: $7,160
Without bonus depreciation:
- Year 1: $12,300
- Year 2: $19,800
- Year 3: $11,900
- Each succeeding year: $7,160
The effect is significant on more expensive cars. A $100,000 sedan would generate a $20,000 first-year MACRS deduction on paper, but the cap holds you to $20,300 with bonus (or $12,300 without). Whatever basis remains after year six keeps depreciating at $7,160 per year until fully recovered, which can stretch the write-off well past the standard six-year window.
Section 179 and the 6,000-Pound Line
Section 179 lets a business deduct the full cost of a qualifying asset in the year it’s placed in service instead of spreading the deduction across years.6Office of the Law Revision Counsel. 26 USC 179 – Election to Expense Certain Depreciable Business Assets For 2026 the overall Section 179 limit is $2,560,000, with phase-out starting at $4,090,000 in total equipment purchases.
The constraint that matters for a car buyer is weight. Passenger cars at or below 6,000 pounds gross vehicle weight rating are still subject to the 280F caps even when Section 179 is elected, so the maximum first-year write-off on a lighter vehicle is $20,300 combining Section 179 and bonus. Vehicles above 6,000 pounds GVWR escape 280F entirely. A qualifying heavy SUV can be expensed up to $32,000 under Section 179’s separate SUV cap for 2026. Heavy pickups and vans that aren’t classified as SUVs can qualify for the full Section 179 deduction without an SUV cap, which in combination with bonus depreciation can zero out the purchase price in year one.
Bonus Depreciation After the One, Big, Beautiful Bill
Bonus depreciation had been phasing down from 100% to 80% in 2023 and was scheduled to keep dropping. The One, Big, Beautiful Bill restored a permanent 100% first-year bonus depreciation deduction for qualified property acquired after January 19, 2025.7Internal Revenue Service. Treasury, IRS Issue Guidance on the Additional First Year Depreciation Deduction Amended as Part of the One, Big, Beautiful Bill For heavy vehicles outside 280F, this means the entire cost can be written off in year one between Section 179 and bonus. For passenger cars under 6,000 pounds, the 280F ceiling still controls, and bonus simply raises the year-one cap from $12,300 to $20,300.
The 50% Business Use Requirement
All of these accelerated deductions require more than 50% business use in the year the vehicle is placed in service.4Office of the Law Revision Counsel. 26 U.S. Code 280F – Limitation on Depreciation for Luxury Automobiles If business use is 50% or less from the start, the vehicle has to be depreciated using the slower Alternative Depreciation System, and Section 179 and bonus depreciation are off the table.
The trap is what happens when business use starts above 50% and later drops below it. The IRS recaptures the extra depreciation: the difference between what you actually deducted (including Section 179 and bonus) and what ADS would have allowed gets added to your ordinary income in the year business use fell short. From that year forward the vehicle switches to ADS. This is the single biggest surprise in business vehicle depreciation, and it hits people who buy an expensive truck for work and then gradually shift it to personal use.
Recapture When You Sell
Depreciation reduces your adjusted basis, so a sale price above that reduced basis produces a gain. Under Section 1245, the gain is taxed as ordinary income up to the amount of depreciation you previously claimed.8Office of the Law Revision Counsel. 26 U.S. Code 1245 – Gain From Dispositions of Certain Depreciable Property A $50,000 truck depreciated by $30,000 has an adjusted basis of $20,000. Sell it for $28,000 and the $8,000 gain is ordinary income, not a capital gain, because it falls within the $30,000 of depreciation taken. Only proceeds above the original $50,000 could qualify for capital gains treatment. Section 179 counts toward this calculation too, so a vehicle fully expensed in year one carries a large recapture exposure the moment you sell it.
How Insurers Calculate Depreciation
When a car is totaled, an insurer does not reimburse what you paid. It pays actual cash value: the cost of replacing the car with a comparable used vehicle, minus depreciation for age, mileage, and condition. This is what the car was worth on the open market immediately before the loss.
Adjusters pull comparable vehicles in your area with similar mileage, trim, and options, then average those prices for a baseline. From there they adjust: down for high miles, worn tires, or cosmetic damage, up for low mileage or recent maintenance. Prior accident damage on a vehicle history report lowers the figure even when the car was properly repaired. Subtract your deductible and that’s the settlement check. Industry valuation tools from Kelley Blue Book and the National Automobile Dealers Association feed into the process using regional sales data and auction results.
Payouts on newer cars often feel low because the first year of depreciation is so steep, and because the comparables an insurer pulls may sit closer to wholesale than retail. Most states let you dispute the valuation with your own comparable sales data or an independent appraisal.
GAP Coverage for the Depreciation Shortfall
Fast first-year depreciation creates a common problem: owing more on the loan than the car is worth. If your insurer pays $20,000 on a total loss but the loan balance is $25,000, you owe the $5,000 difference. GAP insurance (guaranteed asset protection) covers that shortfall up to your outstanding balance. It’s typically inexpensive, and worth considering any time the loan amount exceeds the vehicle’s likely resale value, particularly in the first two to three years of ownership or after rolling negative equity into a new loan.
Diminished Value After an Accident
A properly repaired car still loses market value once an accident shows up on its history. That loss, called diminished value, is separate from repair costs and separate from age-based depreciation. If another driver caused the accident, you can often file a diminished value claim against that driver’s liability insurance to recover the gap between the car’s pre-accident value and its post-repair value.
Rules vary by state. Most require that the other driver be at fault, and many bar diminished value claims against your own insurer for accidents you caused. Vehicles older than about ten years or with prior accident history are harder to claim on because the baseline is already discounted. An independent appraisal before filing strengthens the claim.