Imagine a parent transfers $5 million of Apple stock to their adult daughter, with an original cost basis of $200,000. The parent feels generous. The estate planner nods. But when the daughter sells the stock a year later to buy a house, she owes federal capital gains tax on $4.8 million of embedded appreciation — roughly $1.14 million at the 23.8 percent long-term rate, plus state tax on top. If the parent had instead held the stock until death, the daughter would have inherited it with a fresh basis equal to fair market value. The same sale would have produced zero capital gains tax.
That is the difference between Section 1015 carryover basis and Section 1014 stepped-up basis. For most families, it is the single most consequential decision in estate planning — and most of them get it backward.
The rules have not changed in decades, but the planning calculus shifted dramatically when the One Big Beautiful Bill Act fixed the lifetime gift and estate tax exemption at $15 million per person starting in 2026, indexed for inflation. Under the prior law, the exemption would have collapsed to roughly $7 million after sunset, forcing many families into "use-it-or-lose-it" gifting before year-end 2025. With the exemption now permanent at $15 million, the vast majority of households will never owe federal estate tax — which means the income tax cost of premature gifting is no longer being offset by an estate tax savings that was never going to apply.
This guide walks through the carryover basis rule, the stepped-up basis rule, the dual basis trap for depreciated assets, the gift tax paid basis addition, and the practical framework families should use to decide when to give now versus hold until death.
The Two Rules That Drive the Outcome
Section 1015: Carryover Basis for Lifetime Gifts
When you give an asset during your lifetime, the recipient generally takes your original adjusted basis rather than the fair market value at the time of the gift. The basis "carries over" from donor to donee.
If you bought 100 shares of Microsoft for $10,000 in 2010 and gift them when they are worth $400,000 in 2026, your child's basis in those shares is still $10,000. If the child sells immediately for $400,000, the child realizes a $390,000 long-term capital gain. The holding period also tacks, meaning the long-term character of the gain follows the asset.
The economic effect is straightforward: the embedded gain is not eliminated by the gift, it is simply transferred to the donee, who will pay tax whenever the asset is sold.
Section 1014: Stepped-Up Basis at Death
When an asset is acquired from a decedent, the heir's basis is reset to the fair market value on the date of death (or the alternate valuation date six months later, if the executor elects). All capital appreciation that accrued during the decedent's lifetime is permanently wiped from the tax record.
Using the same Microsoft shares: if you instead held the shares until your death in 2030, when they are worth $600,000, your heir's basis would be $600,000. A sale the next day produces no taxable gain at all. The $590,000 of lifetime appreciation simply disappears for income tax purposes.
This rule applies to most appreciated property — publicly traded stock, real estate, closely held business interests, artwork, collectibles, and partnership interests — as long as the property is included in the decedent's gross estate. It does not apply to assets held in irrevocable trusts where the decedent retained no rights causing estate inclusion, and it does not apply to retirement accounts, which transfer with the decedent's original tax characteristics.
The Dual Basis Rule: Why Gifting Loss Assets Is Almost Always a Mistake
Section 1015 has a quiet but vicious exception for property that has dropped in value below the donor's basis. When fair market value at the time of the gift is less than the donor's adjusted basis, the donee operates under a split system:
- For computing gain, the donee uses the donor's carryover basis (the higher number).
- For computing loss, the donee uses the fair market value at the date of the gift (the lower number).
If the donee's eventual sale price falls between those two numbers, the donee recognizes neither a gain nor a loss. This is sometimes called the "no-gain, no-loss zone."
A Concrete Example
A parent bought rental real estate for $800,000 in 2015. By 2026, it is worth $500,000. The parent gifts the property to a child.
- If the child later sells for $900,000, gain is measured from the carryover basis of $800,000 → $100,000 taxable gain.
- If the child later sells for $400,000, loss is measured from the gift-date FMV of $500,000 → $100,000 deductible loss.
- If the child sells for anywhere between $500,000 and $800,000, there is no recognized gain or loss.
The $300,000 of decline that occurred during the parent's ownership is permanently destroyed for tax purposes the moment the gift is made. The parent forfeits the ability to harvest that loss, and the child cannot use it either.
Planning takeaway: If you own a depreciated asset and were considering gifting it, sell it yourself first, recognize the loss on your own return, and gift the cash proceeds. Almost any other order of operations leaves money on the table.
The Gift Tax Paid Adjustment Under Section 1015(d)
When a donor actually pays federal gift tax on a transfer — meaning the donor has exhausted both the annual exclusion and the lifetime unified credit — the donee gets a partial basis bump under Section 1015(d). The basis is increased by the portion of gift tax that is attributable to the net appreciation in the gifted property:
Increase = Gift Tax Paid × (FMV at gift − Donor's basis) ÷ (FMV at gift)
There are two important caveats:
- The increase cannot push the donee's basis above the fair market value at the time of the gift.
- The adjustment only applies when gift tax is actually paid in cash, not when the gift simply uses up the donor's lifetime exclusion.
Because the OBBBA-set exemption sits at $15 million per individual in 2026 ($30 million for a married couple), most lifetime gifts never trigger any out-of-pocket gift tax. That makes the 1015(d) adjustment largely irrelevant for typical families and meaningful only for the small subset of donors who have already used their full exclusion and are choosing to pay tax to move appreciation outside their estate.
The 2026 Decision Framework
The right answer depends almost entirely on whether the family's net worth is likely to exceed the federal estate tax exemption at the date of death. There are three buckets.
Bucket One: Net Worth Comfortably Below $15 Million (Single) or $30 Million (Couple)
For these households, federal estate tax is not a real concern. The hold-until-death path is categorically better because:
- Holding the asset costs the estate nothing (no federal estate tax will apply).
- Gifting now imposes a 100 percent inherited income tax liability on the embedded gain at the donee's eventual sale.
- Step-up at death eliminates the embedded gain entirely.
Even for families who want to support adult children today, the more tax-efficient move is usually to gift cash (no embedded gain) or to use the annual exclusion gift amount each year (no basis or exemption consequences). Appreciated property should stay on the parent's balance sheet.
Bucket Two: Net Worth Hovering Around the Exemption
This is the hardest case and the one where coordinated income and estate tax modeling pays off. The break-even analysis should compare:
- Hold-for-step-up cost: estate tax at 40 percent on the full date-of-death FMV of the asset.
- Gift-now cost: capital gains tax at up to 23.8 percent on the embedded gain when the donee eventually sells, plus the cost of any future appreciation that ends up in the donee's estate later.
If the asset has a low basis ratio (basis is, say, 5 percent of FMV) and the family is in the 40 percent estate tax bracket, the math usually favors holding for step-up because the estate tax would have applied to only the portion above the exemption. If the asset has a high basis ratio (basis is 70 percent of FMV), the capital gains cost of gifting is small and the estate tax savings on future appreciation can dominate.
Spousal Lifetime Access Trusts, dynasty trusts, and grantor retained annuity trusts can sometimes deliver the best of both worlds — moving future appreciation outside the estate while preserving income tax flexibility — but they require careful drafting and ongoing administration.
Bucket Three: Net Worth Well Above the Exemption
For ultra-high-net-worth families, lifetime gifting of appreciation-prone assets generally still makes sense because every dollar of future appreciation moved out of the estate avoids the 40 percent transfer tax, and the income tax cost on the embedded gain (paid by the donee at sale) is bounded at 23.8 percent federal. The right asset to gift is the one most likely to keep appreciating — venture-backed startup equity, early-stage real estate, growth securities — and the right asset to hold for step-up is the one with the largest existing embedded gain relative to its future appreciation potential.
Common Mistakes That Quietly Cost Families Millions
Gifting low-basis stock to fund a child's home purchase. The parent feels good about a tax-free transfer under the annual exclusion or lifetime exemption, but the child inherits a massive embedded gain that gets recognized at the worst possible time. Gifting cash instead — even if it requires the parent to sell securities and pay capital gains tax — is often neutral or better, because the parent may have a lower bracket, more available losses to harvest, or qualified dividend offsets.
Gifting depreciated property without selling first. The dual basis rule eats the loss. Always sell before gifting if the asset is underwater.
Failing to coordinate with state estate tax. Twelve states and the District of Columbia impose estate or inheritance taxes with exemption thresholds far below the federal $15 million — some as low as $1 million. State-level planning may justify lifetime gifting even when federal estate tax is not a concern.
Forgetting that grantor trust assets do not always get a step-up. The IRS confirmed in Revenue Ruling 2023-2 that assets held in an irrevocable grantor trust outside the grantor's estate do not receive a basis adjustment at the grantor's death. Many families assume otherwise and discover the surprise during the post-death tax return.
Not tracking donor basis records. A gift recipient who cannot prove the donor's original basis is exposed to the IRS treating basis as zero in an audit. Both donor and donee should retain purchase records, improvement records, and prior gift tax returns indefinitely.
What to Do Before Year End
For most families, the right move in 2026 is not aggressive gifting — it is documentation and recalibration.
- Pull a basis inventory. For every appreciated holding, note original purchase price, date, and any improvements or reinvested dividends that affect basis.
- Identify the assets most likely to receive a meaningful step-up. These are the assets to hold until death, not to gift.
- Identify the assets with the highest future growth potential. These are the candidates for lifetime gifting or transfer to dynasty-style trusts if the family is in the estate-taxable bucket.
- Coordinate with state law. A family in New York, Massachusetts, Oregon, or Washington faces a very different calculus than a family in Florida or Texas.
- Revisit any prior gifting plans built around the 2025 sunset. Strategies that assumed a $7 million exemption may no longer be necessary or optimal with the permanent $15 million floor.
Keep Your Financial Records Audit-Ready From Day One
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