Should You Gift Appreciated Stock, Fund a GRAT, or Hold for Step-Up on a $20M Estate? A 5-Question Checklist (September 2026)
Picture a single filer with a $20 million estate. $6 million of it is one stock position bought years ago for $1.5 million. The 2026 federal exemption is $15 million per person, so about $5 million of that estate sits above the line and gets taxed at 40%. Three moves are on the table: hold the stock and let heirs take the step-up in basis, gift it outright now, or put it in a zeroed-out GRAT.
Run it over 10 years at 8% growth and the outright gift saves $2.78 million in federal estate tax. It also costs your heirs $2.73 million in capital gains tax if they sell. The net difference is about $55,000. Same asset, same growth, and the right answer flips depending on one question: will your heirs sell?
That's a constructed example, not anyone's real plan. Below is the full math, followed by a 5-question checklist for deciding whether to act on your own numbers.
What a Resort Stay, a Car Insurance Quote, and Airline Miles Teach You About Estate Math
The sources for this post look unrelated to estate planning. They all illustrate the same mistake: trusting a headline number without checking the conditions behind it.
The headline value versus your value. NerdWallet's sponsored piece, "How I Turned $99 Into a $6,205.32 Luxury Resort Stay," is a roughly 63× headline ($6,205.32 ÷ $99). It rests on the IHG Premier card's 4th-night-free perk plus other benefits. That pays off for someone who books that kind of stay and not for someone who doesn't. A trust headline like "$722,000 saved" works the same way. It's true for one set of inputs and misleading as a general claim.
You only win if you perform. NerdWallet's "Guide to Usage-Based Car Insurance" says the approach can lower costs for safe drivers, but not everyone gets a cheaper rate. A GRAT is a usage-based deal in the same sense. It pays off only if the asset actually outruns the IRS hurdle rate.
Exchange rates differ by vehicle. NerdWallet's "Citi Adds Japan Airlines as Its Newest Transfer Partner" reports a transfer ratio of 1:1 or 1:0.7, depending on the card. Ten thousand points become either 10,000 or 7,000 miles, a 30% haircut, and the transfer is one-way. Moving wealth out of your estate has the same feature. A GRAT hands over only the excess growth (about $1.8M of a $6M asset in the example below). An outright gift hands over the whole asset and all future growth, but heirs inherit your old basis. Funding an irrevocable trust is also a one-way door.
The backdrop. NerdWallet's "Mortgage Rates Today, Monday, September 21: A Little Respite" has mortgage rates holding just above 7%. The Bureau of Labor Statistics' latest indicators show CPI +0.4% in August 2026, unemployment at 4.1%, and payroll employment of +162,000 (preliminary). I'm not forecasting anything from those numbers. They matter for the hurdle-rate discussion later.
The Worked Example: $6M of Stock, Three Paths, 10 Years
Assumptions (all illustrative):
- Single filer, $20M estate, of which $14M is other assets held flat and $6M is the stock
- Stock basis $1.5M, growth 8% per year
- Federal exemption held at $15M (it's indexed to inflation after 2026, so this is slightly conservative)
- Estate tax 40%, capital gains 23.8% (20% plus 3.8% NIIT)
- No state taxes, no discounting, no legal fees
At 8% for 10 years, the stock grows to 6M × 1.08¹⁰ = $12.95M.
| Path | Moved out of estate | Federal estate tax saved | Heirs' basis | Cap gains if sold at year 10 |
|---|---|---|---|---|
| Hold until death | $0 | $0 | Stepped up to $12.95M | $0 |
| Outright gift of $6M | $12.95M | $2.78M | Carryover $1.5M | $2.73M |
| Zeroed-out 10-yr GRAT (assumed 4.8% hurdle) | $1.81M | $722K | Carryover | Up to $430K, worst case |
Hold: the estate reaches $26.95M, and the tax is 40% × ($26.95M − $15M) = $4.78M.
Gift: the estate at death is $14M, tested against the $9M of exemption left after using $6M. That gives 40% × $5M = $2.0M. The saving is 40% of the $6.95M of growth that escaped the estate.
This is the kind of side-by-side Voritanel runs for you, so you don't have to build the spreadsheet yourself.
The Time Horizon Changes the Winner
Here's the outright gift versus holding at three horizons, assuming heirs sell right after your death:
| Years | Stock value | Estate tax saved | Cap gains cost | Net of gifting |
|---|---|---|---|---|
| 5 | $8.82M | $1.13M | $1.74M | −$615K |
| 10 | $12.95M | $2.78M | $2.73M | +$55K |
| 15 | $19.03M | $5.21M | $4.17M | +$1.04M |
If heirs never sell, every row is a pure win for the gift, because the step-up you gave up is worth nothing when there's no sale. If they sell, the gift loses for roughly the first 9.7 years at 8% growth and then pulls ahead.
The break-even comes from setting 40% × (V − $6M) equal to 23.8% × (V − $1.5M). Solving gives V ≈ $12.61M, or about 2.1× the starting value.
But your numbers will differ. A 5% state income tax on the gain moves the break-even out further. A lower basis moves it out too. A spouse who inherits and holds pushes the whole calculation in a different direction. We covered the same tension on a smaller scale in Gift Appreciated Stock or Hold for the Step-Up? The 8-Year Break-Even on a $100,000 Gift.
The GRAT Path: Small Upside, Real Sensitivity
A zeroed-out GRAT doesn't use your exemption, and the tax on gains has a different shape. Here's the math for a 10-year term with an assumed 4.8% IRS 7520 rate. That rate is my placeholder. The sources above don't state the September 2026 rate, so check the published rate for the month you'd fund.
- Annuity payment: $6M × 0.048 ÷ (1 − 1.048⁻¹⁰) ≈ $769,500 per year
- Remainder at 8% growth: ≈ $1.81M to heirs, saving about $722K
- Remainder at 6% growth: ≈ $602K, saving about $241K
- Remainder at 12% growth: ≈ $5.13M, saving about $2.05M
- Remainder at 4.8% growth: essentially zero
That's the usage-based-insurance logic in numbers. The trust costs almost nothing if it underperforms, since you're back where you started minus fees. But it doesn't save much unless the asset really runs. Dying during the term also pulls the assets back into your estate. For how this compares with an installment sale to an IDGT, see When a GRAT Beats an IDGT (and When It Doesn't).
Why a 7%+ Rate Environment Changes the Decision
The 7520 rate is 120% of the federal mid-term AFR, so it follows Treasury yields. Mortgage rates are a loose cousin of that, not the same thing. But if the NerdWallet reading of just above 7% mortgages reflects a generally higher yield environment, three things follow:
- GRATs and installment notes face a higher hurdle. Every extra point of hurdle takes a slice off your remainder.
- Outright gifts don't care. The gift path above has no rate input, so as the hurdle rises, using exemption gets relatively more attractive.
- The BLS prints don't settle it. A +0.4% CPI month annualizes to about 4.9% if it persisted, but one month isn't a trend. Slow inflation also nudges the exemption indexing, though only slightly.
The practical takeaway is to model both a rate that stays put and one that moves against you before you commit, and not to bet on the next Fed meeting.
The 5-Question Checklist: Should You Act Now?
1. Are you actually over your exemption? A single filer has $15M. A married couple can have up to $30M if portability is handled properly. Our $20M single-filer example is exposed, but the same $20M held by a married couple with both exemptions intact owes no federal estate tax. The right answer may be "do nothing, but file the portability election." State thresholds are much lower in places like Massachusetts, so check your state separately. See GRAT vs. IDGT vs. Portability on a $7 Million Estate: Why Massachusetts Residents Still Owe About $588K.
2. How big is the gap between your basis and today's value? In the example it's 4:1 ($6M versus $1.5M). The larger the gap, the more valuable the step-up you'd give up by gifting. A high-basis asset barely has a step-up to lose, so gifting it is much cheaper.
3. Will your heirs sell? If the stock is going to be held for decades, capital gains tax is a deferred cost you may never pay, and the gift looks strong. If they're likely to diversify immediately, the break-even above matters. Be honest here. It's the single biggest swing factor.
4. What growth rate do you honestly expect versus the hurdle? GRAT math is only interesting if growth clearly exceeds the hurdle. A concentrated position might, and a diversified balanced portfolio probably won't. Use a range (6%, 8%, 12%), not one number.
5. Can you live with a one-way door? Like a Citi transfer to Japan Airlines Mileage Bank, an irrevocable gift or trust can't be undone. Do you need this asset for your own income? Do you have state estate tax exposure that changes the gift-versus-hold math? If you're charitably inclined, a charitable remainder trust is a fourth option that sidesteps the immediate capital gain on a sale, as covered in GRAT vs. Charitable Remainder Trust on $4M in Concentrated Stock.
Reading Your Own Answers
- Estate under your exemption (Q1), high basis (Q2), or likely-to-sell heirs (Q3): holding for the step-up often wins, and the cheapest move may be updating documents.
- Over the exemption, low basis, heirs who hold: outright gifting or a grantor-trust strategy tends to look best.
- Over the exemption, strong growth expectations, comfort with an irrevocable structure: a GRAT or IDGT sale becomes worth modeling, with the hurdle rate as your main sensitivity.
These are tendencies, not rules. Change the basis, the state, or the growth rate, and the break-even moves, sometimes by years and sometimes by six figures.
You can model this for your specific situation at Voritanel, including your basis, state, exemption status, and hurdle-rate range.
Where This Leaves You
In the example, the "best" strategy saved between $55,000 and $2.78 million depending on one behavior of your heirs, and the GRAT's savings ranged from roughly zero to $2.05 million depending on growth. Rules of thumb can't resolve a spread like that. The headline figure in a resort stay, an insurance quote, or a trust illustration only tells you what happens under someone else's inputs.
If you want a broader starting point, GRAT, IDGT, or Portability? A 5-Question Decision Framework for Estates Between $5M and $27M covers the structure choice at a higher level. When you're ready to see your own break-even, Voritanel lets you plug in your basis, growth range, state, and rate assumptions and compare hold, gift, GRAT, and IDGT side by side. There's no rush. The math will still be there when you're ready.
This post is educational, not tax or legal advice. The worked example uses simplified, labeled assumptions. Confirm current rates and rules with a qualified estate attorney before acting.
Sources
- How I Turned $99 Into a $6,205.32 Luxury Resort Stay — NerdWallet
- Guide to Usage-Based Car Insurance — NerdWallet
- Mortgage Rates Today, Monday, September 21: A Little Respite — NerdWallet
- Citi Adds Japan Airlines as Its Newest Transfer Partner — NerdWallet
- Major Economic Indicators Latest Numbers — Bureau of Labor Statistics