Section 179 for real estate lets a business immediately expense certain improvements to nonresidential buildings instead of depreciating them over decades, with a maximum deduction of $2,560,000 for tax years beginning in 2026. The catch is that only specific categories of work qualify. Land, residential rentals, and structural additions are out; roofs, HVAC, fire protection, security systems, and qualifying interior renovations to commercial buildings are in.
What Real Estate Qualifies
The statute creates two tracks for real property. Both feed into the same Section 179 deduction, but the eligibility rules differ.
The first track covers four categories of building components installed on nonresidential real property after the building was originally placed in service:
- Roofs, including full replacements and major repairs to an existing commercial roof.
- HVAC systems: heating, ventilation, and air-conditioning equipment.
- Fire protection and alarm systems, meaning sprinklers, fire suppression equipment, and alarm panels.
- Security systems, including surveillance cameras, access control hardware, and intrusion detection.
The improvement must be installed after the building was first placed in service by any person. Components that came with a building when it was originally constructed or purchased new can’t be expensed under this track.
The second track is Qualified Improvement Property, or QIP. QIP covers interior renovations to existing nonresidential buildings: new lighting, plumbing overhauls, updated flooring, interior partition walls, ceiling replacements. The improvement has to be placed in service after the building itself was, and the taxpayer claiming the deduction must be the one who made the improvement. Buying a building and expensing renovations a previous owner completed is not allowed.
Three types of work are specifically excluded from QIP regardless of cost:
- Building enlargements, such as adding square footage, a new wing, or an additional floor.
- Elevators and escalators, whether installed new or replaced.
- Internal structural framework, meaning modifications to load-bearing walls, columns, or similar structural elements.
The line between qualifying interior work and excluded structural change is where most disputes arise. Replacing common-area flooring or installing new interior doors falls comfortably within QIP. Knocking out a load-bearing wall to combine two spaces does not. When a renovation mixes structural and non-structural work, the costs need to be separated so only the eligible portion is expensed. Under the general depreciation system, QIP has a 15-year recovery period, which also makes it eligible for bonus depreciation.
What Doesn’t Qualify
The biggest misconception about Section 179 is that any real estate expense can run through it. Several categories are flatly ineligible.
Residential rental property. Apartment buildings, single-family rentals, and duplexes used as long-term rentals are residential real property and sit outside Section 179’s scope. One narrow exception: short-term rentals with average guest stays under 30 days are often classified as nonresidential for depreciation purposes, which can open the door to QIP treatment on interior improvements. Whether a particular short-term rental qualifies depends on the average length of stay and whether the owner provides substantial personal services like daily cleaning or concierge service.
Land and land improvements. The land itself, parking lots, sidewalks, bridges, and non-agricultural fencing are not Section 179 property. A new parking lot for a commercial building does not qualify simply because the building does.
Property acquired from related parties. Improvements or equipment purchased from a spouse, ancestor, lineal descendant, or certain related entities don’t qualify, even when the property itself would otherwise be eligible.
2026 Deduction Limits and Phase-Out
For tax years beginning in 2026, the maximum Section 179 deduction across all qualifying property is $2,560,000. That figure is the inflation-adjusted version of a $2,500,000 statutory base set for taxable years beginning after 2023.
A phase-out limits the benefit for businesses placing large amounts of qualifying property into service in a single year. The phase-out begins once total qualifying property placed in service exceeds $4,090,000. For every dollar above that threshold, the maximum deduction drops by one dollar. Once total qualifying purchases hit $6,650,000, the deduction disappears entirely. Both the ceiling and the phase-out threshold adjust annually for inflation; the IRS publishes the current figures through a revenue procedure each year.
Business Use and Income Requirements
Two conditions gate the deduction beyond the dollar caps.
The property must be used more than 50% for business. If a building improvement serves both business and personal purposes, only the business-use share of the cost is eligible, and if business use is 50% or below, the property doesn’t qualify at all. This matters mainly for mixed-use properties or situations where an owner uses part of a building personally.
The total Section 179 deduction for the year also cannot exceed combined taxable income from all trades or businesses the taxpayer actively conducts. The rule exists to keep Section 179 from creating or increasing a net operating loss. If a business earns $800,000 in taxable income and places $1,200,000 of qualifying improvements into service, only $800,000 can be deducted this year. Anything blocked by the income limitation carries forward indefinitely, so the full deduction is eventually captured as long as the business generates enough taxable income in future years.
Recapture
Claiming Section 179 creates an ongoing obligation that lasts through the property’s recovery period. If business use drops to 50% or below at any point during that period, part of the deduction gets recaptured: the IRS substitutes standard depreciation for the amount originally expensed, and tax is owed on the difference.
Selling, trading, or giving away Section 179 property can also trigger recapture. On a sale, any gain attributable to the previously expensed amount is recaptured as ordinary income rather than capital gain. This catches owners off guard when they sell a building a few years after expensing a roof replacement or HVAC system. Tracking business-use percentages every year through the recovery period, and modeling recapture before selling, avoids the surprise.
Section 179 or Bonus Depreciation
Both Section 179 and bonus depreciation let you deduct the full cost of qualifying property in year one, but they work differently and interact in ways that matter for planning real estate improvements.
Section 179 is elective asset by asset. You pick which assets to expense and how much. It’s capped at $2,560,000 for 2026, limited by taxable income, and phases out at high spending levels. Unused amounts carry forward.
Bonus depreciation applies automatically to every eligible asset in a given class unless you elect out for the whole class. Following the One Big Beautiful Bill Act signed into law on July 4, 2025, bonus depreciation returned to 100% for property acquired on or after January 20, 2025. There is no dollar cap and no taxable income limitation, and bonus depreciation can create or increase a net operating loss.
When a property qualifies for both, the common approach is to apply Section 179 first to priority assets and let bonus depreciation cover the rest. Section 179 gives more control because it’s chosen asset by asset, while bonus depreciation sweeps an entire property class. For QIP specifically, the 15-year recovery period makes it eligible for both, so the choice often comes down to whether you want the income cap of Section 179 (to avoid an NOL) or the unlimited write-off of bonus depreciation.
How to Claim the Deduction
The Section 179 election is made on IRS Form 4562, Depreciation and Amortization. In Part I, each expensed property is listed separately with a description, the date it was placed in service, its cost, and the amount being expensed. The form also computes the taxable income limitation and any carryforward from prior years.
Form 4562 attaches to whatever return the business files: Schedule C of Form 1040 for sole proprietors, Form 1065 for partnerships, or Form 1120 for corporations. Leaving the form off is one of the easiest ways to lose the deduction, since tax software will typically reject or ignore the election without it.
For each improvement, keep documentation showing:
- The placed-in-service date, meaning the date the improvement was ready and available for use rather than when construction started. Work orders, certificates of occupancy, and contractor completion letters establish this.
- The cost, supported by invoices, contracts, and payment receipts.
- The business-use percentage, meaning the share of time or space used for business rather than personal purposes during the year.
Hold those records for the property’s recovery period plus the statute of limitations on the return. For QIP with a 15-year life, that generally means keeping documentation for at least 18 years.
State Conformity
Federal Section 179 limits don’t automatically apply on state returns. Several states cap the deduction well below the federal amount, some as low as around $25,000, and others conform to the federal deduction but exclude real property from eligibility. A $2,560,000 federal deduction can produce a state add-back of most of that amount, sharply increasing state tax in the year of the claim. Check your state’s current conformity rules before counting on Section 179 savings at the state level.