An investment held for decades carries a hidden tax the whole time it grows. The gap between what was paid and what the asset is now worth is a built-in capital gain, and selling it during life means handing a slice to the IRS. Death changes that calculation completely. When appreciated stock, real estate, or a business passes to an heir, the tax code generally resets its value to the price on the date the owner died, quietly forgiving a lifetime of accumulated gain before the heir ever sells.
How date-of-death value replaces the original cost
The figure that determines capital-gains tax is called basis — usually what the original owner paid, adjusted over time. When an asset moves through an estate, the heir’s basis is generally reset to the fair market value on the date of death, a mechanism the tax code refers to as a step-up. A parent who bought shares for $20,000 that are worth $120,000 at death passes them to a child with a new basis of $120,000. The $100,000 of growth that built up over a lifetime is simply erased for tax purposes.
If the heir then sells near that value, the taxable gain is close to nothing, because gain is measured only from the stepped-up figure forward. The IRS rules on the basis of inherited property spell out this reset, and it applies to most assets that would otherwise carry an unrealized gain — brokerage holdings, rental buildings, land, and a family home alike.
The reset can also cut both ways. An asset that lost value before death steps down to the lower date-of-death price, wiping out a loss the family might otherwise have used. That makes the timing and titling of assets a real decision for older households rather than an afterthought.
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Why community-property states can double the benefit
For married couples, where a couple lives shapes how much of an asset gets the reset. In most states, when one spouse dies, only that spouse’s half of a jointly owned asset steps up to current value; the survivor’s half keeps its original basis. A home bought together decades ago would get half its gain forgiven, leaving the surviving spouse holding built-in gain on the other half if they later sell.
In community-property states, the rule is more generous. Both halves of a qualifying community asset can step up to fair market value when the first spouse dies, so the survivor inherits an almost entirely refreshed basis on the whole property. A widow or widower in one of those states can often sell an appreciated holding shortly afterward with little or no capital-gains tax owed, a break unavailable to a couple in a common-law state.
That geographic split is why the same portfolio can produce very different tax outcomes for two families in otherwise identical situations. It also explains why surviving spouses are frequently advised to look hard at whether to sell soon after a death, while the stepped-up value is still fresh, rather than let an asset appreciate again and rebuild a taxable gain from the new, higher floor. A few states allow married couples to hold property in special community-property trusts to capture the double step-up even where it would not otherwise apply, a planning move that can be worth pursuing well before either spouse dies.
The valuation and recordkeeping that protect the reset
The step-up is only as solid as the number behind it. Because the heir’s basis becomes the date-of-death value, that figure has to be documented, not guessed. For publicly traded securities the price is easy to pin down, but a house, a piece of land, or a private business usually needs a formal appraisal as of the date of death to establish a defensible value. Without it, a later sale can leave the family arguing with the IRS over how much gain is real.
Executors sometimes have the option to value an entire estate as of a date roughly six months after death instead of the day of death, a choice that can matter when markets move sharply in the months after a passing. The IRS guidance on basis lays out how the figure is set and what records support it, and the reset generally does not apply to assets that were already tax-favored, such as a traditional IRA, whose withdrawals stay fully taxable to the heir regardless of when the owner died.
The larger point for older families is that the benefit is automatic but fragile. A lifetime of gain can vanish for tax purposes at death, yet the savings can be lost to a missing appraisal or a poorly titled account. And because the step-up is a recurring target in tax-reform debates, families relying on it are betting on a provision that Congress has repeatedly weighed narrowing — a reason the value of an inherited asset is worth confirming, and documenting, the year it changes hands rather than the year it is finally sold.
This article was researched and drafted with the assistance of artificial intelligence.
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