Depreciation Methods Guide

Understand book vs. tax depreciation and maximize your deductions.

What is Depreciation?

When you buy a piece of equipment, a vehicle, or other long-lived asset, you don't expense the entire cost immediately. Instead, you spread that cost over the asset's useful life—matching the expense to the periods when you're actually using the asset.

This spreading of cost is called depreciation. It's an accounting concept that reduces your reported income over time and, importantly, reduces your taxes.

Key insight: You'll typically track TWO different depreciation amounts for every asset—one for financial reporting (book) and one for taxes. They can be very different, and that's completely normal and legal.

Book Depreciation vs. Tax Depreciation

Book Depreciation (GAAP/Financial Reporting)

This is what shows up on your financial statements. The goal is to reflect economic reality—spreading the cost over the period you actually benefit from the asset.

  • You have flexibility in choosing methods and useful lives
  • Should reflect how the asset actually wears out
  • Typically uses straight-line depreciation
  • Affects your reported profit to investors, lenders, etc.

Tax Depreciation (IRS Rules)

This is what you report to the IRS. The goal is often to minimize taxes by taking deductions as fast as legally allowed.

  • Must follow IRS rules (MACRS, Section 179, Bonus)
  • Often accelerated—bigger deductions in early years
  • Directly affects how much tax you pay
  • The IRS tells you exactly how to calculate it

Having different amounts is normal. Your book depreciation might be $5,000 this year while your tax depreciation is $15,000. The difference creates what accountants call a "deferred tax" item.

Book Depreciation Methods

Straight-Line Depreciation

The simplest and most common method. You take equal depreciation expense every year.

📝 Formula

Annual Depreciation = (Cost - Salvage Value) ÷ Useful Life

Example: A $25,000 delivery van with $5,000 salvage value and 5-year life:

($25,000 - $5,000) ÷ 5 = $4,000 per year

Pros: Simple, predictable, easy to forecast
Cons: Doesn't maximize early tax deductions
Best for: Assets that wear evenly over time; financial reporting purposes

Double Declining Balance (DDB)

An accelerated method that front-loads depreciation. You take more expense in early years, less in later years.

📝 How It Works

Double the straight-line rate, apply to the remaining book value each year.

Same $25,000 van example (5-year life):

  • Straight-line rate: 20% (1/5)
  • DDB rate: 40% (double)
  • Year 1: $25,000 × 40% = $10,000
  • Year 2: $15,000 × 40% = $6,000
  • Year 3: $9,000 × 40% = $3,600
  • And so on...

Pros: Matches reality for assets that lose value quickly
Cons: More complex; lower deductions in later years
Best for: Technology, vehicles, equipment that becomes obsolete

Units of Production

Depreciation based on actual usage rather than time. Great for machinery, vehicles, or equipment with variable use.

📝 Formula

Per-Unit Rate = (Cost - Salvage) ÷ Total Expected Units

Annual Depreciation = Per-Unit Rate × Actual Units Used

Example: A $50,000 machine expected to produce 100,000 units:

Per-unit rate = $50,000 ÷ 100,000 = $0.50

If you produce 15,000 units this year: $0.50 × 15,000 = $7,500 depreciation

Pros: Matches expense to actual usage; fair if use varies
Cons: Requires tracking usage; unpredictable expense
Best for: Manufacturing equipment, delivery vehicles (by mileage)

Tax Depreciation Methods

MACRS (Modified Accelerated Cost Recovery System)

The IRS's standard depreciation system. You don't get to choose—the IRS assigns recovery periods and provides depreciation tables.

Common MACRS Recovery Periods:

  • 3-year: Certain manufacturing tools, tractors
  • 5-year: Computers, office equipment, cars, light trucks
  • 7-year: Office furniture, most machinery and equipment
  • 15-year: Land improvements, qualified leasehold improvements
  • 27.5-year: Residential rental property
  • 39-year: Commercial buildings

For most personal property (not buildings), MACRS uses a modified version of double declining balance, giving you accelerated deductions.

Section 179 Expensing

Instead of depreciating over time, you can deduct the entire cost in the year you buy the asset.

2024 Limits:
Maximum deduction: $1,160,000
Phase-out starts: $2,890,000 in total purchases

Key rules:

  • Can't exceed your business income (can't create a loss)
  • Asset must be used more than 50% for business
  • Qualifying property: equipment, machinery, vehicles, computers, software, some improvements
  • Does NOT apply to buildings (except some improvements)

Best for: Profitable businesses that want immediate deductions

Bonus Depreciation

An additional first-year deduction on top of (or instead of) regular MACRS depreciation.

Current rates (phasing down):

  • 2023: 80%
  • 2024: 60%
  • 2025: 40%
  • 2026: 20%
  • 2027: 0% (unless extended by Congress)

Key differences from Section 179:

  • CAN create a business loss (no income limitation)
  • Applies to new AND used property (if new to you)
  • Remaining cost after bonus goes to regular MACRS

Decision Framework: Which Method to Use?

For Book Depreciation

Most businesses should use straight-line for simplicity and consistency. Only use accelerated methods if the asset truly loses value faster in early years (like technology).

For Tax Depreciation

Generally, maximize deductions as fast as possible:

  1. If you have taxable income to offset: Use Section 179 first (up to the limit), then bonus depreciation, then MACRS
  2. If you have low income this year: Skip Section 179 (it's limited to your income), use bonus depreciation to create a loss you can carry forward
  3. For real estate: You must use straight-line over 27.5 or 39 years (no accelerated options)

💰 Tax Impact Example

You buy $50,000 of equipment. Your tax rate is 25%.

Method Year 1 Deduction Year 1 Tax Savings
Straight-line (5-year) $10,000 $2,500
MACRS (5-year) $10,000 $2,500
Section 179 $50,000 $12,500
Bonus (60%) + MACRS $34,000 $8,500

Common Mistakes to Avoid

  • Not tracking assets separately: Each asset needs its own depreciation schedule
  • Forgetting the in-service date: Depreciation starts when you place the asset in service, not when you buy it
  • Using wrong recovery periods: A computer is 5-year, furniture is 7-year—getting this wrong affects your taxes
  • Missing Section 179 opportunities: Many small businesses don't realize they can expense entire purchases
  • Not reconciling book vs. tax: These should be tracked separately but reconciled to explain differences

Let Lease Easy AI handle the complexity. We track book and tax depreciation side-by-side, identify Section 179 and bonus depreciation opportunities, and generate all the schedules you need for tax time and audits.

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JD

Jordan Davis, CMA

Founder, Lease Easy AI
This guide is for educational purposes only. Consult with your CPA or tax advisor for advice specific to your situation.