What it means
Basis value answers a simple question: when you sell an asset, how much of the money coming in is genuine profit and how much is just the return of your own capital. The tax authority taxes the gain, not the whole sale price, so the basis is the number that stops the same money being taxed twice.
Get it wrong and you either overpay tax or invite a correction later. The starting point is cost, including the extras needed to put the asset into service, such as delivery, installation, non-recoverable duties and professional fees on a property purchase.
A major upgrade that extends the life or capability of the asset is added to the basis, while routine repairs are expensed and leave it unchanged. The distinction between repair and improvement is one of the most argued points in practice.
From there the figure is adjusted year by year. Depreciation or capital allowances claimed reduce it, further capitalised spending increases it, and the running total is called the adjusted basis.
Any decent fixed asset register shows this figure alongside cost and accumulated depreciation. This matters because two businesses holding identical assets can face very different tax bills on sale.
A building that has been depreciated for fifteen years carries a low basis, so a sale at market value produces a large taxable gain even though the owner feels no richer than the day before the sale. Boards planning a disposal therefore model the tax on the gain, not just the cash expected.
The variants worth knowing concern assets that were not bought in a normal transaction. Inherited and gifted assets may take a basis reset to market value at the date of transfer, or may carry over the previous owner's basis, depending on the rules in the jurisdiction.
Record keeping is the practical risk, because a basis that cannot be evidenced with invoices may be treated as low or nil.
In practice
Real-world examples.
Example
A dental practice sells a scanner for $45,000. It cost $120,000 including installation, and $85,000 of depreciation has been claimed, so the adjusted basis is $35,000 and the gain is $10,000. The practice manager budgets tax on the $10,000, not on the $45,000 of proceeds.
Example
A family business inherits a warehouse and the basis is reset to its $1,200,000 market value at the date of transfer. When it sells three years later for $1,350,000, the taxable gain is $150,000 rather than the much larger gain the original owner would have faced. The reset, not the sale price, is what drives the outcome.
Example
A software company capitalises $400,000 of development costs on a platform and amortises $160,000 of it before selling the platform to a competitor for $500,000. The adjusted basis is $240,000, so the gain is $260,000. The finance team evidences every capitalised invoice, because the basis is what shrinks the taxable amount.
Formula
Calculation
Adjusted basis value = original cost + capitalised improvements - accumulated depreciation. Gain on sale = sale proceeds - adjusted basis value.
A print business buys a press for $250,000 and later spends $30,000 on a capitalised upgrade to its feeding system. Over six years it claims $120,000 of depreciation. The adjusted basis is $250,000 + $30,000 - $120,000 = $160,000. Selling the press for $200,000 produces a taxable gain of $200,000 - $160,000 = $40,000, not the $200,000 of cash received, and at a 25% tax rate the tax is 25% of $40,000 = $10,000.Case study
Seen in the real world.
Harbourline Logistics is an illustrative, fictional haulage firm used here to show how basis value drives a decision rather than just a tax return. Its board is choosing between selling a depot for $2,000,000 or refinancing against it. The depot cost $900,000 twenty years ago, $300,000 of capitalised improvements have been added and $500,000 of depreciation has been claimed, so the adjusted basis is $900,000 + $300,000 - $500,000 = $700,000. A sale would therefore crystallise a gain of $2,000,000 - $700,000 = $1,300,000, with tax on that gain reducing the cash available for the new fleet. In this illustrative case the board refinances instead, because borrowing against the depot raises similar cash without triggering the gain. The basis value, a number that had sat quietly in the fixed asset register for two decades, decided the strategy.
Watch out
Common mistakes.
- Using the original purchase price as the basis and forgetting that depreciation claimed has already reduced it.
- Capitalising routine repairs into the basis, or expensing genuine improvements that should have been added to it.
- Keeping no evidence of improvement spending, which leaves the basis unprovable when a disposal is reviewed.
Questions
People also ask.
Is basis value the same as book value?
They are close cousins and often identical, but basis is the tax measure and book value follows the accounting policy, so the two can differ.
Does a loan secured on an asset change its basis?
No, borrowing against an asset does not change what it is treated as having cost, although the interest is a separate deductible expense.
What happens to basis in a part disposal?
The basis is apportioned between the part sold and the part retained, usually on a reasonable value or cost basis, so only the relevant slice is set against the proceeds.
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