What it means
A capital loss is not the same thing as an operating loss. Operating losses come from trading, when the cost of running the business exceeds its revenue, whereas capital losses come from disposing of an asset held for investment or long-term use.
The distinction matters because tax rules almost always treat the two very differently. Nothing happens for tax purposes while a holding merely falls in value.
The loss is unrealised until you actually sell, at which point it becomes realised and enters the calculation. This is why investors talk about paper losses and real losses as separate ideas.
The practical use of a capital loss is offsetting. Losses are first netted against gains of the same kind in the same tax year, and many jurisdictions then allow a limited amount to be set against ordinary income, with the remainder carried forward to future years.
Carried-forward losses are a genuine economic asset even though they rarely appear on the balance sheet at anything like full value. Businesses meet capital losses too, most often on the disposal of property, plant or shares in another company.
The accounts record the shortfall between sale proceeds and carrying value as a loss on disposal, shown separately from trading results so readers are not misled about underlying performance. The tax treatment then follows its own rules, which rarely match the accounting figure exactly.
This creates a technique often called tax-loss harvesting, where an investor deliberately sells a losing position before the year end to bank the loss against gains already taken. Most tax systems block the obvious abuse with a rule that denies the loss if you buy the same asset back within a set window, commonly around thirty days.
The technique itself is legitimate; it is the repurchase timing that needs care.
In practice
Real-world examples
Example 1
A family investment company sells a small stake in a private business for $180,000 having paid $310,000 for it five years earlier. The $130,000 capital loss is carried forward and used two years later against the gain on selling a commercial property.
Example 2
A retailer disposes of a delivery depot for $1,400,000 when its written-down value in the books is $1,650,000. The $250,000 shortfall is a capital loss on disposal and is disclosed separately so readers do not mistake it for a trading result.
Example 3
A private investor holds two funds, one showing a $22,000 gain and one a $14,000 loss. Selling both in the same tax year leaves a net gain of $8,000 to be taxed rather than the full $22,000.
Think of it
Imagine buying a collector bicycle for 500 pounds. A few years later, cycling styles change and you sell it at a garage sale for 300 pounds. The 200 pound difference is your capital loss.
Formula
Calculation
Capital loss = Sale proceeds - Cost basis, where a negative result is the loss
An investor bought shares for $120,000 including dealing costs and later sells them for $85,000. The result is $85,000 - $120,000 = -$35,000, which is a capital loss of $35,000. In the same year the investor had realised $50,000 of capital gains elsewhere, so the net taxable gain becomes $50,000 - $35,000 = $15,000. At a 20% capital gains rate the tax bill falls from $10,000 to $3,000, a saving of $7,000 produced purely by the timing of one sale.Case study
Seen in the real world
Larkspur Holdings is an invented family investment vehicle used purely as an illustrative example. In one year it sold a warehouse at a $420,000 gain and was facing a substantial tax charge in a year when cash was already tight.
Its adviser pointed out that Larkspur also held a technology fund standing at a $180,000 unrealised loss that the family had long since decided to exit. Selling it before the year end realised the loss and cut the net gain to $240,000. The family then waited well beyond the repurchase window before reinvesting in a different fund, so the loss stood. Nothing about the underlying investments changed; only the sequencing did, and the tax bill fell accordingly.
Watch out
Common mistakes
- Believing a falling share price creates a deductible loss, when the loss only counts once the asset is actually sold.
- Selling at a loss and buying the identical holding back a few days later, which most tax systems disallow under wash sale or bed-and-breakfasting rules.
- Confusing a capital loss with a trading loss, which usually has entirely different offset rules and time limits.
Questions
People also ask
Can capital losses be set against ordinary salary or business income?
Usually only to a limited annual amount, if at all; most systems restrict them to offsetting capital gains, with the balance carried forward.
Do capital losses expire?
In many jurisdictions they can be carried forward indefinitely, but the rules differ and some impose time limits or restrict use after a change of ownership.
Should tax ever drive the decision to sell?
Tax should inform the timing, not the investment case; selling a holding you still believe in simply to book a loss usually costs more than it saves.