Accounting & Reporting

Depreciation Methods Compared

Four legal ways to spread the same cost, each producing a different profit, a different tax bill, and a different story about the business.

  • Intermediate
  • 8 min total
  • 12 chapters

What decision this helps you make: Which depreciation method and useful life to use for book purposes, how to read someone else's choice, and when a change in estimate is a judgement call rather than a red flag.

What this topic is

Depreciation spreads the cost of a long-lived asset across the years it is used, instead of expensing all of it on the day you buy it. The methods differ only in the SHAPE of that spreading: even across the years, front-loaded, or tied to how hard the asset is worked.

Why it matters

The method never changes how much cash left the building, but it changes reported profit every single year, it changes the tax bill through a separate set of rules, and it changes the picture a buyer or lender sees. Two identical businesses can report very different profits with nothing between them but a depreciation policy.

Who should learn it

Owners of equipment-heavy or vehicle-heavy businesses, anyone reading someone else's financials, and finance staff who need to explain why book profit and taxable income are never the same number.

What you will understand

  • How straight-line, declining balance, units of production, and sum-of-the-years-digits actually compute
  • Why the tax deduction follows a different set of rules than the book charge
  • What a change in useful life does to reported profit, and why it is legal
  • Where depreciation quietly misleads: EBITDA, asset-heavy buyouts, and fully depreciated assets still in use

Prerequisites

Common misconception

"Accelerated depreciation saves tax." It moves tax. The total deduction over an asset's life is the same under every method. What changes is the year you take it. Front-loading is worth real money because a deduction now is worth more than the same deduction in year five, but treating it as a permanent saving is how businesses get surprised by a large tax bill in year four on a machine that is still running fine.