What Is Tax Depreciation? Writing Off Business Assets Over Time

Tax depreciation lets businesses recover the cost of tangible business assets (equipment, vehicles, buildings, subject to rules) over time through deductions on tax returns, rather than expensing the entire purchase immediately, unless immediate expensing elections like Section 179 or bonus depreciation apply for qualifying property.

Key Takeaways

• MACRS assigns prescribed recovery periods and methods to different asset classes, from 5-year computers to 39-year commercial buildings
• Section 179 and bonus depreciation can allow immediate or accelerated first-year write-offs, but each has distinct limits and qualification rules
• Selling a depreciated asset triggers recapture, meaning part of the gain is taxed as ordinary income rather than capital gains

Tax depreciation differs from book depreciation on financial statements; small businesses must track both when lenders want GAAP books but taxes follow the IRC.

Disclaimer: Depreciation rules change with legislation.

Why Depreciation Exists

If you buy a durable asset with a multi-year life, tax policy generally matches expense recognition to periods benefited, with many accelerated options to incentivize investment.

MACRS (Common Federal Framework)

Many tangible assets use Modified Accelerated Cost Recovery System (MACRS) with prescribed lives and methods. Class life depends on asset type—computers vs. Furniture vs. Nonresidential real property differ dramatically.

Section 179 Deduction

Section 179 may allow immediate expensing up to limits for qualifying property purchased for use in an active trade or business, subject to phase-outs and taxable income constraints. Not all assets qualify; SUVs and real property have special rules.

Bonus Depreciation

Bonus depreciation (percentage set by law per year) can allow additional first-year write-off for qualifying new and sometimes used property, again subject to complex rules.

179 vs bonus stacking order and state conformity matter. This is CPA spreadsheet territory.

Basis and Placed-in-Service

Depreciation starts when an asset is placed in service, not necessarily the purchase date if installation lags. Basis generally equals cost plus capitalized improvements, minus certain credits/grants.

Salvage Value and Useful Life (Tax vs Book)

Financial accounting might use salvage value and management useful lives. Tax MACRS often ignores salvage for the prescribed method and uses IRS lives, hence book-tax differences.

Depreciation Recapture

When you sell a depreciated asset, portion of gain may be recaptured as ordinary income (e.g., Section 1245/1250 concepts). Do not assume the entire gain is long-term capital gain.

Link to capital gains planning when exiting assets.

Listed Property and Luxury Autos

Vehicles and certain listed property face caps and personal use adjustments—mileage logs matter; see mileage tracking.

What You Cannot Depreciate

Land is not depreciated. Inventory is not depreciated—it is COGS. Intangibles may use amortization under different sections (e.g., Section 197 for certain purchased intangibles); distinct rules.

Bookkeeping Alignment

Your books should track fixed assets with purchase docs, in-service dates, and disposals. Lenders and buyers due diligence these schedules during business planning exits.

Common Mistakes

• Expensing assets that must be capitalized
• Missing bonus/179 elections or applying them wrong
• Ignoring personal use percentage on vehicles
• Failing to dispose assets in software when scrapped (phantom depreciation continues)

State Conformity

States may decouple from federal bonus/179—total tax planning requires both layers.

Quick FAQ

• Can I expense a laptop immediately? Maybe, de minimis, 179, and bonus rules interact; price and entity facts control.
• Does book depreciation match tax? Often no, book follows your policy; tax follows IRC. Reconcile M-1/M-2 style adjustments with help.

How to Claim Depreciation on Your Assets

Maintain a fixed asset register with purchase date, placed-in-service date, cost, and asset class, update it when equipment moves locations or gets sold. Before year-end, ask your CPA whether 179/bonus elections fit this year’s income picture; last year’s answer may differ. When you dispose of gear, capture sale price and date immediately so recapture math does not rely on memory 18 months later.

Snapshot: common depreciation “gotchas”

Used property may still qualify for bonus in some years. Do not assume new-only without checking. Mixed-use assets need business percentage support, photos and logs beat estimates in audits. Repairs vs. Improvements classification changes whether you expense now or capitalize, gray areas are CPA calls. Short tax years (mid-year entity changes) adjust conventions, software defaults may be wrong without pro setup.

When you lease equipment, lessor/lessee depreciation rights differ from purchases. Contracts matter as much as invoices.

Mid-year convention tables can front-load or smooth deductions in ways that surprise first-time buyers, ask your preparer to show the year-by-year schedule for big buys.

Listed property with heavy personal use can disallow or defer deductions. Track mileage and purpose like you would for an audit already scheduled.

Goodwill and other intangibles follow different rules than tangible assets. Do not assume one schedule fits all.

Summary

Tax depreciation spreads (or via elections, front-loads) deductions for qualifying business assets under MACRS, Section 179, and bonus rules; distinct from book depreciation. Track basis, placed-in-service dates, and disposals; involve a CPA when buying heavy equipment, buildings, or vehicles with mixed use. Getting depreciation right lowers current tax legally while avoiding painful recapture surprises later.

How Depreciation Lowers Your Taxable Income

Depreciation choices directly affect your cash flow and tax bill every year you own equipment, vehicles, or buildings. Electing Section 179 or bonus depreciation on a large purchase can dramatically lower the current year's tax liability, freeing up cash for operations, but it also means smaller deductions in future years. Before any major asset purchase, ask your CPA to model both immediate expensing and standard MACRS schedules so you understand the multi-year trade-off.

Depreciation Schedules and Documentation

Maintain a fixed asset register that includes purchase date, placed-in-service date, cost basis, asset class, and depreciation method for every depreciable item. Store the original invoice or receipt, any installation documentation, and a photo of the asset in a digital folder organized by year. When you dispose of or sell equipment, record the sale date, sale price, and buyer information immediately so recapture calculations are accurate. Reconcile your asset register against your accounting software quarterly to catch phantom assets that were scrapped but never removed from the books.

Related Articles

• Guide to Business Tax Deductions for Small Businesses
• What Is a Tax Write-Off? Deductions vs Credits vs Refunds
• Cash vs Accrual Accounting: Which Method Is Right for Your Business?

Frequently Asked Questions

What is the difference between Section 179 and bonus depreciation?

Section 179 lets you deduct the full cost of qualifying assets in the year of purchase up to an annual dollar limit, while bonus depreciation allows you to deduct a percentage of the cost with no dollar cap but with phase-down rules over time. Section 179 can be used selectively on specific assets, whereas bonus depreciation applies to all eligible assets unless you elect out.

Can I depreciate a used asset I purchased for my business?

Yes, used assets qualify for depreciation as long as they are new to your business and used for business purposes. Both Section 179 and bonus depreciation now apply to used property (since the Tax Cuts and Jobs Act), so you can often deduct the full cost of used equipment in the year you buy it.

What happens to depreciation when I sell a business asset?

When you sell a depreciated asset for more than its adjusted basis (original cost minus accumulated depreciation), you must report the gain, and some or all of it may be taxed as depreciation recapture at ordinary income rates rather than capital gains rates. This recapture is reported on Form 4797 and can create a larger-than-expected tax bill if you have heavily depreciated the asset.