Step-Up in Basis: Why Heirs Inherit Stocks Tax-Free

When a parent buys a stock for $1,000 and it grows to $50,000 before their death, the heir inherits that $50,000 position. But here's the remarkable part: if that heir sells the stock the very next week, there is no capital gains tax owed on the $49,000 of appreciation. The IRS essentially forgives the entire gain. This isn't an obscure loophole. It's a core feature of the U.S. tax code, codified in Section 1014, known as the step-up in basis at death.

How the Step-Up Works: The Mechanism

Basis is the IRS's shorthand for the amount you've invested in an asset. When you buy 100 shares of Apple at $150 per share, your basis is $15,000. If you later sell those shares for $20,000, your capital gain is $5,000. That's the difference between what you paid and what you received.

But when you inherit an asset, Section 1014 resets your basis to the fair market value of that asset on the date of death (or six months later if the executor elects the alternate valuation date). This new basis becomes your starting point for calculating future gains or losses. If you sell immediately after inheriting, there is nothing to tax because your basis equals the value you just received.

The economic effect is dramatic. A lifetime of gains vanishes from the tax perspective, wiped clean by the act of inheritance. The deceased taxpayer never paid tax on those gains, and the heir never will—unless the asset appreciates further after inheritance.

A Real Example: The Tech Stock That Multiplied 70 Times

In 1998, a parent buys 800 shares of a high-flying tech stock at $4.50 per share. The initial investment is $3,600. For 27 years, the stock climbs. By May 2025, when the parent passes away, each share is worth $312. The inherited position is now worth $249,600.

Without the step-up, the heir would inherit that $249,600 position with a cost basis of $3,600—leaving a deferred gain of $246,000. If the heir sold immediately, they would owe capital gains tax on that entire $246,000 gain, potentially triggering a federal and state tax bill exceeding $60,000 depending on the heir's income and location.

But Section 1014 changes this completely. The heir's new basis is $249,600 (the value on the date of death). If they sell one week later at $312 per share, the gain is zero. The heir walks away with $249,600 of proceeds and pays no federal capital gains tax on the appreciated amount. The entire gain evaporates.

Why Gifting That Stock During Life Is Usually Worse

This comparison reveals why the timing of wealth transfer matters dramatically. Suppose the parent, wanting to be generous, gifts those 800 shares to their child in 2020 when the stock was worth $80,000. The child receives the shares with a carryover basis of $3,600—the parent's original cost. The gift itself is not taxable (thank the annual exclusion and lifetime exemption), but the child's tax burden is now locked in.

If the child sells that stock five years later at $312 per share ($249,600 total), they owe capital gains tax on $246,000 of gain. At the 15% long-term capital gains rate, that's $36,900 in federal tax alone—before any state taxes. Compare this to the zero federal tax owed if the same stock is held until death and inherited at the stepped-up basis.

The numbers are brutal. By gifting during life, the parent reduced the child's wealth by tens of thousands of dollars in taxes that could have been avoided entirely. The parent was generous with the gift but inadvertently transferred the tax liability along with it.

The Community Property Double Step-Up in Nine States

Married couples in community property states (Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin) get an additional benefit. All property earned during the marriage is considered owned equally by both spouses, regardless of whose name is on the title or who earned the income. When one spouse dies, both the deceased's half and the surviving spouse's half receive a step-up in basis to date-of-death value.

Return to the tech stock example. Suppose the parent lived in California and bought the stock during their marriage. When they pass, the stock steps up to $249,600. But the surviving spouse's half also steps up, even though they never paid any of the original $4.50 cost. Both halves are now valued at date-of-death prices. For married couples in these states, this is one of the most valuable hidden tax benefits in the Code.

Common-law states do not offer this double step-up. Only the deceased spouse's shares step up; the surviving spouse's basis remains tied to the original purchase price. This creates a strong incentive for couples in community property states to understand and rely on this rule in their estate planning.

What Does NOT Get a Step-Up

The step-up applies to most investments: stocks, bonds, mutual funds, real estate, art, and other appreciated property. But several asset types are excluded, and this matters enormously for planning.

• IRAs and 401(k)s pass to beneficiaries with income in respect of a decedent (IRD) treatment. Withdrawals are fully taxable as ordinary income.
• Annuities and certain deferred compensation arrangements do not step up. The entire accumulated gain is ordinary income to the beneficiary.
• Savings bonds and Series I bonds may be partially excluded, depending on the timing and the bonds' maturity.
• Inherited installment contracts retain their deferred gain; the beneficiary assumes the seller's tax liability.

This is why many estate planners recommend funding IRAs and 401(k)s with appreciated investments and leaving non-qualified stocks to heirs. The tax treatment is reversed: tax-deferred accounts are tax-inefficient to inherit, while appreciated stocks are tax-efficient.

The Alternate Valuation Date: A Two-Year Window

When an estate is large enough to require a federal estate tax return (over $13.61 million in 2024 for a single person), the executor can elect the alternate valuation date. Instead of using the fair market value on the date of death, the estate is valued six months after death. All inherited assets step up (or step down) to their value on that later date.

In a down market, this can be valuable. If stocks plummet between the death date and six months later, using the alternate valuation date locks in lower values, reducing both estate tax and the heir's future gain. But the decision is all-or-nothing: if the executor elects the alternate valuation date, all assets in the estate are measured on that date, not a date chosen asset by asset.

The Tax Policy Behind the Step-Up

Why does the IRS allow this? The step-up at death exists partly for administrative simplicity—valuing every inherited asset at death avoids complex carryover basis tracking—and partly because of historical capital gains taxation policy. The United States has long treated death as a realization event for gift tax purposes but not for income tax. The step-up is the income tax equivalent of that philosophy: gain realized at death is not taxed during lifetime.

Critics argue that the step-up represents tens of billions of dollars in forgone tax revenue annually, disproportionately benefiting wealthy families with large stock portfolios. Proposals to repeal or limit the step-up surface regularly in Congress, though full repeal remains unlikely due to political opposition from affluent taxpayers and small business owners who rely on the step-up to preserve family businesses.

Using the Step-Up Strategically

If you are managing a portfolio for yourself or anticipating an inheritance, the step-up should influence your decisions. First, be wary of gifting highly appreciated assets during your lifetime unless you have compelling non-tax reasons to do so. The tax cost is usually higher than you expect. Second, if you live in a community property state and are married, understand that the step-up is automatic and powerful; leverage it by holding appreciated assets in community property form. Third, ensure that heirs understand what they're receiving: if they inherit an IRA rather than a stock portfolio, the tax consequences are fundamentally different.

For estate planners, the step-up suggests a strategic approach to asset location. Fund IRAs with conservative, low-growth investments that don't need to step up. Leave appreciated growth stocks to heirs in taxable accounts where the step-up will do maximum good. For households large enough to face estate taxes, the interplay between the step-up and the estate exemption is critical; sometimes it makes sense to pay modest estate tax in order to let a larger portfolio step up, reducing income taxes on beneficiaries downstream.

The step-up in basis is not a loophole or an accident. It is a deliberate feature of the tax code that can save your heirs tens of thousands of dollars—or more—in capital gains taxes. Understanding it, and structuring your portfolio with it in mind, is one of the highest-impact decisions a high-net-worth household can make.