Section 1245 property is any property that is or has been of a character subject to the allowance for depreciation provided in section 167 and that falls into one of the classes listed at 26 U.S.C. 1245(a)(3). Two classes carry almost all of it: personal property, and other tangible property, not including a building or its structural components, whose adjusted basis reflects depreciation for a period in which it was used as an integral part of manufacturing, production or extraction, or of furnishing transportation, communications, electrical energy, gas, water or sewage disposal services. The class matters while the asset is in service too, because section 179 property has to be either section 1245 property or, at the election of the taxpayer, qualified real property (26 U.S.C. 179(d)(1)(B)). What it settles most sharply is how the gain is taxed on the way out.
What the Statute Puts in the Section 1245 Property Class
Beyond personal property, the tangible-property class also reaches a research facility used in connection with those same activities, and a facility used in connection with them for the bulk storage of fungible commodities, including commodities in a liquid or gaseous state. Four narrower classes follow: real property whose adjusted basis reflects amortization adjustments under a named list of provisions, a single purpose agricultural or horticultural structure, a storage facility that is not a building or its structural components used in connection with the distribution of petroleum or any primary product of petroleum, and any railroad grading or tunnel bore (26 U.S.C. 1245(a)(3)).
Personal property is wider here than the usual shorthand suggests. The regulation defines it as tangible personal property, as that term is defined in 26 CFR 1.48-1(c), and intangible personal property, and it adds that a leasehold of section 1245 property is in the class too while a leasehold of land stays out (26 CFR 1.1245-3(a) and (b)).
An amortizable section 197 intangible on the schedule is therefore inside the class rather than outside it, because any amortizable section 197 intangible is treated as property of a character subject to the allowance for depreciation provided in section 167 (26 U.S.C. 197(f)(7)).
Buildings and Their Structural Components Are the Main Exclusion
Both terms are defined rather than left to intuition. The regulation assigns them the meanings they carry in 26 CFR 1.48-1(e) (26 CFR 1.1245-3(c)).
A building there generally means any structure or edifice enclosing a space within its walls, usually covered by a roof, whose purpose is, for example, to provide shelter or housing, or to provide working, office, parking, display or sales space, and the regulation names apartment houses, factory and office buildings, warehouses, barns, garages, railway or bus stations and stores as examples. It does not include a structure that is essentially an item of machinery or equipment, and the structures named as outside the term include oil and gas storage tanks, grain storage bins, silos and blast furnaces. Structural components include walls, floors and ceilings and their permanent coverings, windows and doors, the components of a central air conditioning or heating system, plumbing fixtures, and electric wiring and lighting fixtures (26 CFR 1.48-1(e)).
A building was never entirely outside the class. Subparagraph (C) already reaches so much of any real property, other than property described in subparagraph (B), whose adjusted basis reflects amortization adjustments under the provisions it names, so an amortized slice of real property has long sat inside the class, and the single purpose agricultural or horticultural structure of subparagraph (D) is a second long standing route. What 2025 added was subparagraph (G), which brings qualified production property in (26 U.S.C. 1245(a)(3)). That property is the portion of nonresidential real property used by the taxpayer as an integral part of a qualified production activity, placed in service in the United States or any possession of the United States, whose original use commences with the taxpayer, whose construction begins after January 19, 2025 and before January 1, 2029, and which the taxpayer designates in the election and places in service before January 1, 2031 (26 U.S.C. 168(n)(2)(A)).
A qualified production activity is the manufacturing, production or refining of a qualified product, and the activities do not count unless they result in a substantial transformation of the property comprising the product, with production itself limited to agricultural production and chemical production (26 U.S.C. 168(n)(2)(D) and (E)).
Space used for offices, administrative services, lodging, parking, sales activities, research activities, or software development or engineering activities is outside qualified production property, along with other functions unrelated to the manufacturing, production or refining of tangible personal property (26 U.S.C. 168(n)(2)(C)).
Where the Classification Is Made and What a Wrong Code Costs
The classification is made on the fixed asset schedule, in the class code assigned when the asset is added, years before anyone sells anything. Say a small manufacturing client’s schedule carries a lathe, the office furniture, the plant building, the central heating system in that building, and a silo holding grain before processing. The lathe and the furniture are personal property, so both sit in the class. The building does not, and neither does the heating system, because it is a structural component, unless the sole justification for installing it is a temperature or humidity requirement essential to the operation of other machinery or the processing of materials or foodstuffs, which takes it back out of the term (26 CFR 1.48-1(e)(2)). The silo is outside the definition of a building, and it enters the class if it is used for the bulk storage of fungible commodities in connection with production.
The other place the split is made deliberately is a cost segregation study, which moves parts of a building’s cost off the long recovery period and onto section 1245 lives (Cost Segregation Audit Techniques Guide), and what that trade costs at the exit is worked through in commercial real estate accounting.
A wrong class code is not cosmetic. On section 1245 property the depreciation slice of the gain comes back as ordinary income (26 U.S.C. 1245(a)(1)), and that slice is depreciation recapture, with the gain above it treated as section 1231 gain when the property has been held for more than 1 year (26 U.S.C. 1231(b)(1)). Coding a structural component as equipment overstates the deduction for years and then changes the character of the gain at sale.
A gain on the disposition is figured in Part III of Form 4797, where line 25 computes the section 1245 slice, and a loss on depreciable trade or business property held more than 1 year starts in Part I instead (IRS, Instructions for Form 4797 (2025)). By then the class code on the fixed assets register has been carried for years.
Section 1245 Property Versus 1250 and 1231
Section 1250 property is defined against this one: any depreciable real property that is not section 1245 property (26 U.S.C. 1250(c)). An office building, a warehouse and residential rental property are the ordinary examples, and how the two sections treat a gain differently is set out in depreciation recapture. Section 1231 is not an alternative to either, because it characterizes whatever gain is left after recapture, and that leftover is section 1231 gain.
If fixed asset schedules and disposition workpapers are the work that slips when a firm is short on capacity, a trial task puts a block of that work through Accountably’s review chain before any live file depends on it.
