A business security system doesn’t have one depreciation life. Different parts of the same installation land in different MACRS classes: cameras, recorders, and monitors generally sit in the 5-year class; alarm keypads and control units often fall into the 7-year class; conduit, fencing, and other interior or land improvements can run 15 years; and anything left as a structural part of the building defaults to 27.5 years for residential rental or 39 years for nonresidential real property. That layered result is the standard security system depreciation life for tax purposes, but it rarely matters in practice, because Section 179 and the 100% bonus depreciation restored by the One, Big, Beautiful Bill Act let most businesses deduct the full cost the year the system goes into service.
Recovery Periods by Component
The IRS treats a security system as a set of components, not a single asset. How each piece is classified determines its recovery period under the General Depreciation System (GDS).1Internal Revenue Service. Publication 946 (2025), How To Depreciate Property The cleanest test is whether a component is tangible personal property (removable equipment) or a structural part of the building (embedded wiring, hardwired panels tied into the building’s electrical system).
5-Year Property
Electronic equipment with a distinct, identifiable function falls in the 5-year class. Security cameras, network video recorders, DVRs, monitors, and dedicated monitoring servers are treated as qualified technological equipment.1Internal Revenue Service. Publication 946 (2025), How To Depreciate Property This is where most of the dollar value of a typical system sits.
7-Year Property
The 7-year class is the MACRS catch-all for tangible personal property that doesn’t fit elsewhere. Intercom handsets, alarm keypads, motion detectors, and control units that are more than simple peripherals but still removable often land here. The line between 5-year and 7-year property can be blurry, and a cost segregation study is the most reliable way to sort components.
15-Year Property
Two categories of security spending fall into the 15-year class. Interior improvements to a nonresidential building that don’t enlarge it, add an elevator, or change its structural framework can qualify as Qualified Improvement Property (QIP).2Office of the Law Revision Counsel. 26 USC 168 – Accelerated Cost Recovery System Running new conduit through existing walls, cutting access points for card readers, and mounting brackets that become part of the interior finish can qualify. Outdoor infrastructure classified as a land improvement — perimeter fencing, camera poles cemented into the ground, and concrete pads for guard booths — also gets 15 years.1Internal Revenue Service. Publication 946 (2025), How To Depreciate Property
27.5-Year Property (Residential Rental)
A security system installed in a residential rental building follows the building itself: 27.5 years under GDS, using the mid-month convention.3Internal Revenue Service. Publication 527, Residential Rental Property It does not qualify for the Section 179 real property election, which is limited to nonresidential buildings. Landlords who want faster recovery should look at cost segregation to pull out any components that qualify as 5-year or 7-year personal property.
39-Year Property
Any component classified as a structural element of a nonresidential building, and not separated through cost segregation, defaults to 39 years. That’s the outcome to avoid. Once a whole installation is dropped into a single 39-year line, unwinding it later requires an accounting method change with the IRS.
Section 179 Expensing
Section 179 lets a business deduct the full cost of qualifying property in the year it’s placed in service, rather than depreciating it over the recovery periods above. Security systems are explicitly eligible, both as tangible personal property and as qualifying improvements to nonresidential real property.4Internal Revenue Service. Topic No. 704, Depreciation The IRS groups them with roofs, HVAC, and fire protection systems as improvements that qualify even when treated as real property.
The One, Big, Beautiful Bill Act expanded the deduction starting in 2025. For tax years beginning in 2026, the maximum deduction is $2,560,000, and the phase-out doesn’t begin until qualifying property placed in service exceeds $4,090,000. Those thresholds are now permanent and adjust for inflation. The prior ceiling was roughly $1.2 million.
Constraints still apply. The property must be used more than 50% for business. The deduction cannot exceed net taxable income from active trades or businesses for the year, and any excess carries forward. The election is made on Form 4562, filed with the return for the year the system is placed in service.5Internal Revenue Service. About Form 4562, Depreciation and Amortization
Bonus Depreciation
Bonus depreciation allows an immediate write-off of qualifying property with a MACRS recovery period of 20 years or less.1Internal Revenue Service. Publication 946 (2025), How To Depreciate Property That covers 5-year, 7-year, and 15-year security components. Unlike Section 179, there’s no dollar cap and no taxable-income limitation; bonus depreciation can create or increase a net operating loss.
The percentage had been phasing down: 100% through 2022, 80% in 2023, 60% in 2024, and 40% for 2025 under prior law. The One, Big, Beautiful Bill Act, signed in 2025, restored a permanent 100% for qualified property acquired after January 19, 2025.6Internal Revenue Service. Treasury, IRS Issue Guidance on the Additional First Year Depreciation Deduction Amended as Part of the One, Big, Beautiful Bill For a system placed in service in 2026, the full cost of every component with a 20-year or shorter recovery period is deductible in year one.
Bonus depreciation is automatic. It applies unless the taxpayer elects out for an entire property class on a timely filed return. A business expecting significantly higher income in a future year might elect out to preserve the deductions, but most have no reason to.
Stacking Section 179 and Bonus Depreciation
Businesses commonly use both. Section 179 is applied first, up to the taxable-income limit. Bonus depreciation then covers whatever basis remains, without regard to income. For a $150,000 system placed in service in 2026, a profitable business could deduct the entire amount in year one under either provision alone; the combination matters when taxable income is tight, because Section 179 absorbs what it can and bonus depreciation handles the rest without hitting the income cap.
When ADS Applies Instead
The Alternative Depreciation System (ADS) uses longer recovery periods and straight-line depreciation. A business must use ADS for security equipment that is used predominantly outside the United States, financed with tax-exempt bonds, leased to a tax-exempt entity, or classified as listed property used 50% or less for business.1Internal Revenue Service. Publication 946 (2025), How To Depreciate Property Businesses that elect out of the Section 163(j) interest deduction limit must also use ADS for real property, including any security components classified as nonresidential real property or QIP. ADS property does not qualify for bonus depreciation.
Leased Systems Are Different
If the arrangement is a true lease, the monthly payments are deductible as rent, and the business never depreciates the equipment or claims Section 179.7Internal Revenue Service. Income and Expenses 7 Many “lease” agreements, though, are conditional sales contracts: they transfer title after a set number of payments, include a bargain purchase option, or charge far more than fair rental value. The IRS treats those as purchases, meaning the lessee is the owner for tax purposes and should be depreciating the system rather than deducting payments.
Recapture When You Sell or Replace the System
Every dollar of depreciation on security equipment creates a potential tax bill later. When you sell, trade in, or dispose of depreciated components, Section 1245 requires you to recapture the depreciation by treating part of the gain as ordinary income rather than capital gain.8Internal Revenue Service. Publication 544 (2025), Sales and Other Dispositions of Assets
The recapture amount is the lesser of the total depreciation claimed (including any Section 179 or bonus depreciation) or the gain realized on the disposition. If you fully expensed a $50,000 camera system under Section 179 and later sold it for $8,000, the entire $8,000 is ordinary income because the depreciation claimed exceeds the gain. Gain above the recaptured amount is a Section 1231 gain, which may qualify for long-term capital gains rates. Recapture is reported on Part III of Form 4797.8Internal Revenue Service. Publication 544 (2025), Sales and Other Dispositions of Assets
A system you fully expensed has an adjusted basis of zero, so any sale proceeds trigger ordinary income recapture. The time value of the upfront deduction usually still wins, but the tax hit at replacement time catches owners off guard.
State Conformity
Federal depreciation doesn’t automatically flow through to state returns. States range from full conformity with federal bonus depreciation and Section 179 to complete decoupling, and some conform with a delay or cap the amount of bonus depreciation allowed. Claiming 100% bonus depreciation federally may still leave you depreciating the same system over multiple years for state income tax. Check your state’s current conformity before filing.