Accelerated depreciation is a set of tax methods that let a business write off the cost of equipment, vehicles, buildings, and other long-lived assets faster than they physically wear out. Instead of spreading the deduction evenly across the asset’s recovery period, you claim more of it in the first years of ownership and less later on. For property placed in service in 2026, the most powerful form of this strategy is 100% bonus depreciation, which lets qualifying businesses deduct the entire cost of eligible property in year one.
How It Differs From Straight-Line Depreciation
Straight-line depreciation divides an asset’s cost equally across every year of its recovery period. A $50,000 machine with a five-year life produces a $10,000 deduction each year, five years running. Accelerated methods push more of that total deduction into the early years and leave less for the later ones.
The lifetime deduction is the same either way. What changes is the timing, and timing has real value: a dollar of tax saved this year is worth more than a dollar saved five years from now. Businesses that invest heavily in equipment can put those early savings back into operations, payroll, or additional purchases. The tradeoff is that annual deductions shrink as the asset ages, which means higher taxable income later. Lower taxes now, higher taxes later. That’s the bargain.
MACRS: The Federal Framework
Most business assets in the United States are depreciated under the Modified Accelerated Cost Recovery System, which has been the default federal framework since 1986.1Cornell Law Institute. MACRS MACRS assigns every asset class a fixed recovery period and depreciation method, so you’re not guessing how fast a purchase can be written off.
Common recovery periods:2Internal Revenue Service. Publication 946, How To Depreciate Property
- 3-year property: over-the-road tractor units and certain specialized tools
- 5-year property: automobiles, trucks, computers, and office machinery like copiers
- 7-year property: office furniture, fixtures, desks, and safes
- 15-year property: qualified improvement property (interior renovations to nonresidential buildings, excluding enlargements, elevators, and structural framework changes)
- 27.5-year property: residential rental buildings
- 39-year property: nonresidential commercial buildings
These periods are fixed by federal law regardless of how long you personally plan to keep the asset. Classifying property incorrectly can produce penalties or force you to file a correction later.
What Qualifies
To be depreciable, property must be used in your business or to produce taxable income, have a useful life beyond the current year, and wear out or become obsolete over time.2Internal Revenue Service. Publication 946, How To Depreciate Property Machinery, vehicles, furniture, equipment, and buildings other than land all fit.
What Doesn’t
Land never depreciates because it doesn’t wear out. Inventory is excluded because it’s held for sale, not for use. Property acquired and disposed of in the same year doesn’t qualify either.
Section 179: Immediate Expensing
Section 179 lets you deduct the full purchase price of qualifying equipment in the year you place it in service. For tax years beginning in 2026, the maximum Section 179 deduction is $2,560,000. That ceiling phases out dollar-for-dollar once total qualifying purchases exceed $4,090,000 in a year. For SUVs, the Section 179 deduction is capped at $32,000 regardless of the vehicle’s cost.3Internal Revenue Service. Rev. Proc. 2025-32
The critical limitation: your Section 179 deduction can’t exceed your taxable business income for the year. If your business earned $200,000 and you bought $300,000 in equipment, your Section 179 deduction is capped at $200,000. The unused portion carries forward, but it can’t create a net loss. This income limitation is where Section 179 and bonus depreciation part ways.
Bonus Depreciation Back to 100%
Bonus depreciation had been phasing down since 2023, dropping from 100% to 80%, then 60%. The One, Big, Beautiful Bill Act, signed into law on July 4, 2025, reversed that phasedown and restored a permanent 100% first-year deduction for qualifying property acquired after January 19, 2025.4Internal Revenue Service. One, Big, Beautiful Bill Provisions Property placed in service in 2026 is fully deductible in year one.5Internal Revenue Service. Interim Guidance on Additional First Year Depreciation Deduction
Unlike Section 179, bonus depreciation has no dollar cap and no taxable income limitation. A business that buys $10 million in qualifying equipment can deduct all of it, and the deduction can create or increase a net operating loss. Bonus depreciation applies automatically to eligible property unless you elect out, which some businesses do when they expect to be in a higher tax bracket in future years.
The two rules stack. A common approach is to apply Section 179 first (especially to assets with lower dollar caps, like SUVs), then let bonus depreciation cover the rest. Ordering matters because Section 179 is limited by taxable income while bonus depreciation isn’t.
Conventions That Shrink the First-Year Deduction
MACRS doesn’t hand you a full year of depreciation just because you bought an asset on December 30th. Conventions standardize when property is treated as placed in service.
The half-year convention is the default for most personal property. It treats every asset as placed in service at the midpoint of the year regardless of the actual purchase date. Buy a machine in February or November, and you get the same first-year deduction: half of what a full year would produce.6eCFR. 26 CFR 1.168(d)-1 – Applicable Conventions, Half-Year and Mid-Quarter Conventions
The mid-quarter convention kicks in when more than 40% of your total depreciable property purchases for the year are placed in service during the last three months. It exists to prevent businesses from gaming the half-year convention by loading purchases into December. When it applies, each asset is treated as placed in service at the midpoint of the quarter it was acquired, which reduces the first-year deduction for those late purchases.6eCFR. 26 CFR 1.168(d)-1 – Applicable Conventions, Half-Year and Mid-Quarter Conventions
Real property uses a mid-month convention, treating the building as placed in service at the midpoint of the month you start using it.
Vehicle and Listed Property Limits
Passenger vehicles face annual depreciation ceilings that override the normal MACRS percentages. For a passenger vehicle placed in service in 2026 with bonus depreciation applied, the first-year cap is $20,300. Without bonus depreciation, it drops to $12,300.7Internal Revenue Service. Depreciation Limitations for Passenger Automobiles Placed in Service During Calendar Year 2026 These limits keep passenger cars from generating the same outsized deductions as heavy equipment.
Listed property, which includes passenger vehicles and property that lends itself to personal use, carries a business-use test: you must use the asset more than 50% for qualified business purposes. If business use drops to 50% or less in any year, you lose access to accelerated depreciation and must switch to straight-line over the longer Alternative Depreciation System recovery period. You also have to recapture the excess depreciation already claimed in prior years and report it as income.2Internal Revenue Service. Publication 946, How To Depreciate Property The recapture surprise most often catches owners of vehicles that gradually shift toward personal use.
What Goes Into Your Cost Basis
Your cost basis is the amount you get to depreciate. It’s more than the sticker price. Sales tax, freight, installation, testing, and excise taxes all get added.8Internal Revenue Service. Publication 551, Basis of Assets Miss any of these components and you leave deductions behind.
Under MACRS, salvage value is treated as zero, so you don’t subtract an estimated residual value before calculating depreciation. Keep invoices, receipts, and freight bills as permanent records; the IRS can ask you to substantiate basis years after the purchase.
Filing and Recordkeeping
Depreciation and Section 179 deductions go on IRS Form 4562, attached to your main return.9Internal Revenue Service. Instructions for Form 4562 Sole proprietors file it alongside Schedule C on Form 1040. Corporations attach it to Form 1120. Partnerships and S corporations file a separate Form 4562 for each business activity. If you’re only continuing to depreciate assets placed in service in prior years and aren’t claiming Section 179 or bonus depreciation for the first time, you generally don’t need to file Form 4562 again; the deduction goes directly on the applicable schedule.
Keep supporting documentation (purchase receipts, basis calculations, convention worksheets) for at least three years after you file the return for the last year you claim depreciation on the asset.10Internal Revenue Service. How Long Should I Keep Records? For a seven-year asset, that can mean holding records for a decade or more. Accuracy-related penalties for understated tax run 20% of the underpayment.11Office of the Law Revision Counsel. 26 USC 6662 – Imposition of Accuracy-Related Penalty on Underpayments
Depreciation Recapture When You Sell
Accelerated depreciation reduces your tax basis in the asset. When you sell for more than that adjusted basis, the IRS wants some of those earlier deductions back. That’s depreciation recapture, and it’s the back end of the trade.
For personal property like equipment and vehicles, Section 1245 treats the gain attributable to prior depreciation as ordinary income, taxed at your regular rate rather than the lower capital gains rate.12Office of the Law Revision Counsel. 26 US Code 1245 – Gain From Dispositions of Certain Depreciable Property If you bought a machine for $100,000, claimed $60,000 in depreciation, and sold it for $80,000, the $40,000 gain (sale price minus $40,000 adjusted basis) is all ordinary income because it doesn’t exceed the $60,000 of depreciation you took. For real property, unrecaptured depreciation is taxed at a maximum rate of 25%.13eCFR. 26 CFR 1.453-12 – Allocation of Unrecaptured Section 1250 Gain
Sales get reported on Form 4797, which calculates the ordinary income portion and any remaining capital gain.14Internal Revenue Service. Instructions for Form 4797 – Sales of Business Property The more aggressively you depreciated, the larger the potential recapture. That doesn’t make accelerated depreciation a bad deal; the time value of earlier deductions usually outweighs the eventual recapture. It does mean you should model the after-tax proceeds before selling.
State Rules Don’t Always Match
Federal rules don’t automatically carry over to your state return. A majority of states decouple from federal bonus depreciation to some degree, so the 100% federal write-off may need to be partially or fully added back when calculating state taxable income. Some states also cap Section 179 well below the federal limit. Operating in multiple states can mean maintaining a separate depreciation schedule for each one. Check your state’s conformity rules before assuming a large federal deduction will produce proportional state savings.