Depreciation in Accounting: What It Is and How to Calculate It

Depreciation is an accounting method that spreads the cost of a tangible asset over its useful life. Instead of recording the full purchase price as an expense in the year you buy a piece of equipment or a vehicle, you deduct a portion each year until the asset is fully expensed or reaches its salvage value. This approach follows the matching principle under Generally Accepted Accounting Principles (GAAP), which requires costs to be recognized in the same periods as the revenues they help generate.

Depreciation matters because it affects two critical areas at once: it reduces taxable income on your tax return, and it keeps your balance sheet accurate by reflecting the declining value of your long-term assets. For businesses that manage invoices, track expenses, and monitor their financial health closely, understanding depreciation ensures that profit figures and asset values tell the truth.

What Can Be Depreciated?

The IRS lays out three requirements an asset must meet to qualify for depreciation:

1. You must own it. The asset must belong to you or your business. Leased property generally cannot be depreciated by the lessee (though leasehold improvements often can).
2. You must use it in business or to produce income. Personal-use property does not qualify. If an asset is used partly for business and partly for personal purposes, only the business-use percentage is depreciable.
3. It must have a useful life of more than one year. Items consumed or worn out within a single year are expensed immediately as operating costs.

Depreciable Assets -- Common Examples

Tangible assets:

• Vehicles (cars, trucks, delivery vans)
• Machinery and manufacturing equipment
• Office furniture (desks, chairs, shelving)
• Computer hardware (laptops, servers, monitors)
• Buildings used for business (offices, warehouses, retail space)
• Rental property (both residential and commercial)

Intangible assets:

• Patents
• Copyrights
• Purchased software (not SaaS subscriptions)

Note: intangible assets are technically subject to amortization, which uses the same logic as depreciation but applies to non-physical assets.

Assets That Cannot Be Depreciated

• Land -- it does not wear out or become obsolete. Land is the one fixed asset with an indefinite useful life.
• Inventory -- current assets held for sale, not for long-term use.
• Investments -- stocks, bonds, and similar financial instruments.
• Personal property -- a car used exclusively for family errands does not qualify.
• Collectibles -- art, coins, memorabilia.

Why Depreciation Matters

Tax Benefits

Depreciation is a non-cash deduction. It reduces taxable income without requiring an actual cash outflow in the current period. The IRS allows several accelerated methods and special provisions -- including Section 179 expensing and bonus depreciation -- that let small businesses deduct large portions of an asset's cost in the first year.

Accurate Financial Reporting

Without depreciation, a company's income statement would show an enormous expense in the year it buys a major asset and no expense in subsequent years, even though the asset continues to generate revenue. Depreciation smooths that cost over time, giving stakeholders a more realistic view of profitability.

Asset Replacement Planning

Tracking accumulated depreciation tells you how much economic value remains in your assets. When net book value approaches zero, it signals that replacement is coming -- and that you should budget for it.

Common Depreciation Methods

1. Straight-Line Depreciation

The simplest and most widely used method. It allocates the same expense amount to each year of the asset's useful life.

Formula:

Annual Depreciation = (Asset Cost - Salvage Value) / Useful Life

Example: A delivery van costs $42,000, has a $6,000 salvage value, and a useful life of 6 years.

Annual depreciation = ($42,000 - $6,000) / 6 = $6,000 per year

After six years, the van's book value on the balance sheet will equal its $6,000 salvage value, and no further depreciation is recorded.

2. Modified Accelerated Cost Recovery System (MACRS)

MACRS is the depreciation method the IRS requires for most business property placed in service after 1986. It assigns each asset to a property class (3-year, 5-year, 7-year, and so on) and applies a declining-balance method that front-loads deductions.

Formula:

Depreciation = Cost Basis x MACRS Percentage (from IRS tables)

MACRS is advantageous because it generates larger deductions in the early years of an asset's life, accelerating the tax benefit.

3. Double Declining Balance

This accelerated method records higher depreciation in the early years and lower amounts later. It applies twice the straight-line rate to the asset's declining book value each year.

Formula:

Annual Depreciation = (2 / Useful Life) x Book Value at Beginning of Year

Example: Using the same $42,000 van with a 6-year life:

• Year 1: (2/6) x $42,000 = $14,000
• Year 2: (2/6) x $28,000 = $9,333
• Year 3: (2/6) x $18,667 = $6,222

Depreciation continues until the book value reaches the salvage value, at which point the method switches to straight-line for the remaining years.

4. Units of Production

This method ties depreciation to actual usage rather than time. It is ideal for assets whose wear is driven by output -- a printing press that deteriorates based on pages printed, or a truck that wears out based on miles driven.

Formula:

Depreciation per Unit = (Cost - Salvage Value) / Total Estimated Units of Production

Period Depreciation = Depreciation per Unit x Units Produced in Period

Section 179 and Bonus Depreciation

The IRS offers two provisions that allow businesses to accelerate deductions beyond standard depreciation schedules:

• Section 179 lets you deduct the full cost of qualifying assets (equipment, vehicles, software) in the year they are placed in service, up to an annual dollar limit. For tax year 2025, the limit is $1,250,000.
• Bonus depreciation allows a percentage of the asset's cost to be deducted in the first year on top of normal depreciation. The percentage has been phasing down from 100% under the Tax Cuts and Jobs Act.

These provisions are especially valuable for small businesses that make significant capital purchases and want to reduce their current-year tax liability.

How Depreciation Appears on Financial Statements

• Income statement: Depreciation expense is listed as an operating expense, reducing operating income and net income.
• Balance sheet: Accumulated depreciation is a contra-asset account that reduces the gross value of fixed assets to show net book value.
• Cash flow statement: Because depreciation is a non-cash expense, it is added back to net income in the operating activities section when using the indirect method.

Understanding where depreciation shows up -- and the fact that it reduces reported profits without reducing cash -- is essential for interpreting financial statements accurately.

Related Articles

• How to Calculate Depreciation
• Straight-Line Depreciation: Explanation and Example
• Tax Depreciation: The Impact of Depreciation on Taxes
• Is Accumulated Depreciation a Current Asset?