What Is a Section 179 Expense and How Does It Work?

A Section 179 expense is an election that lets a business deduct the full purchase price of qualifying equipment, vehicles, and software in the year the property is placed in service, rather than depreciating it over several years. For the 2026 tax year, a business can expense up to $2,560,000 in qualifying purchases under this rule. The One, Big, Beautiful Bill Act of 2025 roughly doubled the prior statutory limits, making Section 179 one of the more generous capital-investment incentives available to small and mid-sized businesses.

How the Deduction Works

Without Section 179, most business equipment has to be depreciated over its useful life under the Modified Accelerated Cost Recovery System. A $200,000 machine with a seven-year recovery period produces deductions spread across those seven years. Section 179 collapses that timeline. You deduct the full $200,000 in the year you put the equipment to work.¹

The cash-flow effect is the point. A business that owes $50,000 in tax can cut that bill sharply in the same year it invests in growth, instead of waiting years for depreciation deductions to trickle in.

The deduction is an election, not automatic. You choose which qualifying assets to expense and how much of each asset’s cost to deduct. Any portion you don’t expense follows regular depreciation rules. That flexibility matters when your taxable income is close to the limits below.

2026 Deduction and Investment Limits

Three caps govern how much you can actually deduct in 2026:

Maximum deduction of $2,560,000. This is the most you can expense across all qualifying property placed in service during the year.²
Phase-out threshold of $4,090,000. Once your total qualifying purchases for the year cross this amount, the $2,560,000 cap shrinks dollar-for-dollar. A business that buys $5 million in qualifying equipment loses $910,000 of the deduction, leaving a maximum of $1,650,000.²
Taxable income limit. The deduction cannot exceed your net taxable income from all active trades or businesses for the year, and it cannot create or increase a net operating loss. If you expense $300,000 but your business earns only $200,000, you deduct $200,000 now and carry the remaining $100,000 forward to a future profitable year.¹

All three limits adjust annually for inflation.

What Property Qualifies

To qualify, property must be tangible, depreciable, purchased for use in the active conduct of a business, and placed in service during the tax year you claim the deduction.¹ “Placed in service” means the asset is ready and available for its intended use, not just delivered.

Common qualifying property:

Manufacturing equipment, tools, and other tangible business machinery.
Office furniture, computers, and servers.
Off-the-shelf software sold under a nonexclusive license. Custom software built for a single user does not qualify.
Business vehicles, subject to the vehicle rules below.
Roofs, HVAC, fire protection, alarm, and security systems installed in a nonresidential building after the building was originally placed in service.¹

Used equipment qualifies as long as it is new to your business and acquired by purchase.

What Doesn’t Qualify

Several categories are excluded, and some of them regularly catch owners off guard:

Land and land improvements such as parking lots, fences, swimming pools, and landscaping.³
Inventory held primarily for resale.
Property used mainly for lodging, including most residential rental property.
Investment or rental property acquired only for income production rather than active business use.³
Property bought from a spouse, ancestor, or lineal descendant.¹
Gifts and inherited property. Only purchased assets qualify.¹

Property leased to others by a noncorporate business also generally fails to qualify, though corporations follow a different rule on that point.

Vehicles and the SUV Cap

Vehicles have their own set of rules. Passenger vehicles under 6,000 pounds are subject to annual luxury-auto depreciation limits that hold the first-year deduction well below the full purchase price. Heavier vehicles escape those caps but run into a different one.

For SUVs and crossovers with a gross vehicle weight rating between 6,001 and 14,000 pounds, the Section 179 deduction is capped at $32,000 for 2026.² The remaining cost follows regular depreciation. Vehicles over 14,000 pounds, such as heavy-duty trucks and large commercial vans, are not subject to the SUV cap and can be fully expensed up to the general $2,560,000 limit. The weight that matters is the manufacturer’s gross vehicle weight rating, not curb weight.

The More-Than-50-Percent Business Use Rule

An asset must be used more than 50 percent for business in the year it is placed in service to qualify for Section 179 at all.¹ If you buy a $40,000 truck and use it 70 percent for business, you can expense only the business portion, $28,000.⁴

The test is not one-time. If business use drops to 50 percent or below in any later year, recapture rules apply and you owe back part of the tax benefit. A contemporaneous usage log is the simplest protection during an audit.

Recapture: When You Owe the Deduction Back

Taking the deduction is not the end of the story. If business use falls to 50 percent or below in a later year, or if you sell or otherwise dispose of the property before the end of its normal depreciation period, you must recapture part of the deduction by reporting it as ordinary income.¹

The recapture amount equals the Section 179 deduction you originally claimed, minus the depreciation you would have been entitled to on that amount through the current year had you never made the election. Recapture is reported on Part IV of Form 4797, Sales of Business Property.⁵ It flows to ordinary income on whatever return you used to claim the original deduction.

Vehicles trip people up here most often. A truck that was 80 percent business in year one can drop to 40 percent by year three as personal use grows, and the IRS expects a recapture calculation at that point.

Section 179 vs. Bonus Depreciation

These two deductions overlap enough that business owners routinely confuse them. After the One, Big, Beautiful Bill Act restored 100-percent bonus depreciation for property acquired after January 19, 2025, both let you write off the full cost in year one.⁶ The differences matter for planning:

Section 179 cannot create a net operating loss. Bonus depreciation can. If equipment costs exceed business income, bonus depreciation lets you generate a loss to carry forward, while Section 179 simply pauses the excess until a profitable year.
Section 179 maxes out at $2,560,000 for 2026. Bonus depreciation has no dollar ceiling.²
You pick exactly which assets and how much to expense under Section 179. Bonus depreciation applies automatically to all eligible property unless you elect out of an entire class.
Section 179 applies first and reduces the asset’s depreciable basis. Bonus depreciation then applies to whatever basis remains. Regular MACRS depreciation covers anything left after both.

For most small businesses well under the phase-out threshold, the practical result is similar. The distinction matters when you want to manage how much taxable income you report in a given year, or expense some assets while depreciating others.

How to Claim the Deduction

The election is made on Form 4562, Depreciation and Amortization, attached to your tax return for the year the property is placed in service.⁷ Part I of the form covers Section 179 and asks for a description of the property, its cost (limited to the business-use portion), and the amount you elect to expense.⁸

Sole proprietors and single-member LLCs attach Form 4562 to Form 1040. C corporations file it with Form 1120. Partnerships and S corporations file it with their entity return, and the deduction passes through to partners or shareholders on Schedule K-1.⁹ In a pass-through, both the entity and each owner must independently satisfy the dollar limit, investment limit, and taxable income limit, so a partner whose share exceeds their personal taxable business income has to carry the excess forward even if the entity itself was profitable enough to support the full deduction.

The return must be filed by the standard deadline, April 15 for most individual and calendar-year filers, with a six-month extension available to October 15.¹⁰ You can also make or change the election on a timely filed amended return. Under current law you can revoke an election for any property, but the revocation is permanent for that asset and that tax year.¹ You cannot flip back and forth between expensing and depreciating the same asset.

State Tax Differences

Federal and state Section 179 limits often do not match. Many states cap their own deduction at a lower amount or have not updated their codes to reflect the expanded federal limits. Caps as low as $25,000 exist in several states, so you could expense $2,560,000 federally and only $25,000 on your state return for the same equipment. Check the rules for any state where you file if it decouples from federal depreciation.

Record-Keeping

The IRS expects documentation for every asset you expense. At minimum, keep purchase invoices showing cost and vendor, proof of the date the property was placed in service, and records supporting your business-use percentage.¹¹ For vehicles and mixed-use property, a contemporaneous usage log is the strongest evidence during an audit.

The standard retention rule is three years after filing, but that clock resets when you dispose of the asset because you have to calculate gain or loss then.¹² As a practical matter, hold Section 179 records for as long as you own the property, plus at least three years after the return reporting its sale. Filing errors tied to Section 179 can trigger an accuracy-related penalty of 20 percent of any resulting underpayment.¹³

1
Office of the Law Revision Counsel. 26 USC 179 – Election to Expense Certain Depreciable Business Assets
2
Internal Revenue Service. Revenue Procedure 2025-32 – 2026 Inflation Adjustments
3
Internal Revenue Service. Publication 946 – How To Depreciate Property
4
Internal Revenue Service. Topic No. 510 – Business Use of Car
5
IRS.gov. 2025 Instructions for Form 4797 – Sales of Business Property
6
Internal Revenue Service. Notice 2026-11 – Interim Guidance on Additional First Year Depreciation Deduction Under Section 168(k)
7
Internal Revenue Service. Form 4562 – Depreciation and Amortization
8
Internal Revenue Service. About Form 4562 – Depreciation and Amortization
9
Internal Revenue Service. 2025 Instructions for Form 4562
10
Internal Revenue Service. When to File
11
Internal Revenue Service. What Kind of Records Should I Keep
12
Internal Revenue Service. How Long Should I Keep Records
13
Office of the Law Revision Counsel. 26 USC 6662 – Imposition of Accuracy-Related Penalty on Underpayments