CapEx vs. OpEx: why the truck isn't an expense
You bought a truck in March for $48,000 cash. At the end of the month you open the P&L expecting to see a crater, and instead net income is down about $800. Meanwhile the bank account is very clearly $48,000 lighter. Something looks broken.
Nothing is broken. You did not incur an expense; you traded one asset (cash) for another asset (a truck). The expense arrives later, in slices, over the years the truck is actually working for you. That is capitalization, and misunderstanding it is why so many owners think their financial statements are lying to them.
The test: does the benefit outlive the year?
The rule is about timing, not size. If what you bought will help you earn money for more than about a year, it is a capital expenditure and it goes on the balance sheet. If it is consumed in the current period, it is an operating expense and it hits the P&L now.
Fuel for the truck is opex — burned this month, gone. The truck is capex — it will still be hauling in year four. A repair that keeps the truck running is opex; a new engine that extends its life by three years is capex. Most businesses also set a dollar floor, commonly $2,500, below which they just expense everything regardless, because tracking a $300 asset for five years costs more in effort than the accuracy is worth.
| Year 1 | If expensed | If capitalized |
|---|---|---|
| Cash paid | $48,000 | $48,000 |
| Hits the P&L | $48,000 | $9,600 |
| Assets on the balance sheet | — | $38,400 |
| Reported net income | $12,000 | $50,400 |
| Cash in the bank | $62,000 | $62,000 |
Depreciation is the expense arriving on schedule
Once the truck is on the balance sheet, depreciation is the mechanism that moves it onto the income statement a piece at a time. A $48,000 truck with a five-year useful life becomes a $9,600annual expense, or $800 a month — which is exactly the dip you saw in March.
The logic is matching: the truck earns revenue for five years, so its cost should reduce profit across those same five years. Charging the whole thing to March would make March look catastrophic and years two through five look better than they are. Neither picture would be true.
Cash out in March
$48k
all at once
Expense in March
$800
one month of depreciation
Expense per year
$9.6k
for five years
Why this trips up cash planning
Here is the practical consequence, and it is the one that actually costs people money. Depreciation is an expense that consumes no cash, and a capital purchase is cash that consumes no expense. The two are permanently out of sync, which means your profit and your bank balance can move in opposite directions for entirely legitimate reasons.
- A profitable year can leave you broke. Buy three trucks and your P&L shows a great year while the cash is gone. This is the single most common version of profitable-but-broke.
- A loss year can be cash-flow positive. Heavy depreciation on assets bought years ago drags reported profit negative while cash keeps building. On paper you are losing money; in the account you are fine.
- Loan payments are not an expense either. If you financed the truck, only the interest portion hits the P&L. The principal repayment is cash leaving with no expense attached, which catches almost everyone.
This is why the cash flow statement exists. It takes net income, adds depreciation back because no cash moved, and subtracts the actual capital purchases — reconciling the profit story to the bank story.
What about the tax deduction?
Tax rules run on a separate track from your books, and they are far more generous about timing. Provisions like Section 179 and bonus depreciation can let you deduct much or all of a qualifying asset in the year you buy it, even while your financial statements depreciate it over five years.
That is not a contradiction — it is two sets of books serving two purposes. Your financial statements are trying to show what the business actually earned. The tax return is following a code written partly to encourage investment. Expect the numbers to differ, and expect your accountant to keep a schedule reconciling them. Where the deduction lands is a conversation worth having before you buy, not in March of the following year.
The habit worth building
When you are about to spend real money, ask two separate questions and do not let them blur: how much cash leaves and when, and how much expense hits the P&L and when. For anything you can hold in your hand and use next year, those answers will be different. Plan the cash from the first one and read the profit from the second, and your statements will stop seeming like they disagree with your bank account.
See what a report like this looks like on your own numbers.
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