Net Unrealized Appreciation: The Cost-Basis Line That Decides If It’s Worth It (2026)

A retiree with $400,000 of company stock sitting in a 401(k) has two doors. Door one — the ordinary rollover — costs nothing today. Door two costs $65,600 in federal tax the moment it opens. Most articles about that second door treat it as free money. Run the numbers and it isn’t: at a 22% ordinary rate and a 15% capital gains rate, the rollover catches back up in about eight years.

That second door is the net unrealized appreciation election, and whether it’s worth walking through comes down to a single number your plan administrator already has on file: the cost basis of your employer stock. This post gives you the break-even formula, three worked scenarios at different basis levels, the conditions that move the break-even, and the four mistakes that disqualify people before they ever get to the math.

What Net Unrealized Appreciation Actually Does to Your Tax Bill

Anything that leaves a traditional 401(k) is normally taxed as ordinary income. It doesn’t matter that the money grew as a capital gain inside the plan — the plan wrapper converts it. A $400,000 stock position that cost $80,000 to accumulate produces $400,000 of ordinary income on the way out.

Internal Revenue Code Section 402(e)(4) carves out an exception for employer securities. If you distribute the shares in kind as part of a lump-sum distribution after a qualifying event, the tax splits in two:

• The cost basis — what the plan paid for the shares — is taxed as ordinary income in the year of the distribution.
• The appreciation above that basis — the net unrealized appreciation — is taxed at long-term capital gains rates, and not until you actually sell the shares.

Two details make this better than it first sounds. Under IRS Notice 98-24, the NUA portion is always treated as long-term regardless of how long the plan held the shares. And under Treasury Regulation 1.411-8(b)(4)(ii), the NUA gain escapes the 3.8% net investment income tax that would otherwise apply to a large capital gain.

For 2026, per IRS Rev. Proc. 2025-32, long-term gains are taxed at 0% up to $49,450 of taxable income for single filers ($98,900 married filing jointly), 15% up to $545,500 ($613,700 MFJ), and 20% above that. Ordinary income at the same time runs through seven brackets topping out at 37% above $640,600 single / $768,700 MFJ. That rate gap is the entire prize.

The Net Unrealized Appreciation Break-Even Formula

Here’s the formula in one line. Call the stock’s market value V, the cost basis B, your ordinary rate t_o, and your long-term capital gains rate t_c:

Immediate tax cost = (B × t_o) + ((V − B) × t_c)

NUA after-tax proceeds = V − immediate tax cost

Rollover after-tax value in year n = V × (1 + r)ⁿ × (1 − t_o,future)

The NUA path starts ahead because part of the gain gets the lower rate. The rollover path starts behind but compounds on a pre-tax balance. Somewhere the lines cross. Your job is to figure out whether that crossing point falls before or after you actually need the money.

What most write-ups skip: the basis fraction B/V barely moves the immediate tax bill, but it moves it in the direction people expect — lower basis, lower upfront cost. What genuinely decides the outcome is your future ordinary rate, which is why this decision belongs in the same conversation as your tax-advantaged accounts order of operations rather than being made in isolation on the day you retire.

Three Scenarios: $400,000 of Employer Stock at Different Basis Levels

All three assume a 60-year-old, married filing jointly, in the 22% ordinary bracket now and in retirement, paying 15% on long-term gains, with 7% annual pre-tax growth. The NUA path is modeled at 5.95% after-tax growth (7% reduced by the 15% rate); the rollover path compounds at the full 7% and is taxed at 22% on withdrawal.

Look at the fourth column. Going from 50-cent basis to 5-cent basis — a tenfold difference in basis — only cuts the immediate tax bill from $74,000 to $61,400. That’s a 17% reduction for a 90% change in basis. The reason is that the NUA gain gets bigger as the basis shrinks, and that gain still owes 15% the moment you sell.

Now the honest comparison. If you rolled everything to an IRA and liquidated it today at 22%, you’d net $312,000. At 20-cent basis, NUA nets $334,400. The election is worth about $22,400 in year one — real money, roughly 5.6% of the position. But hold the rollover instead of liquidating it, and by year eight the tax-deferred compounding has erased that lead.

Eight years is not a long time for a 60-year-old. That’s the part the “NUA is free tax savings” framing gets wrong, and it’s the same category of error as assuming a lower expense ratio always wins — the mechanism is real, the magnitude depends entirely on your time horizon.

What Moves the Break-Even (And What Doesn’t)

Four variables shift the crossover point meaningfully. Basis is only one of them.

Your future ordinary rate. This is the biggest lever by a wide margin. Rerun the 20-cent scenario assuming your retirement withdrawals will land in the 24% bracket instead of 22%, and the crossover moves out to year 10. Rerun it assuming a 12% bracket — a plausible outcome for a retiree living mostly on Social Security and a modest portfolio — and the rollover wins immediately. There is no year in which NUA comes out ahead, because you’d have voluntarily paid 22% on the basis to avoid a 12% bill later.

Whether you sell right away. The capital gains tax on the NUA portion isn’t due until you sell. Hold the shares and you keep the deferral — which is the whole reason the rollover normally wins. But holding means keeping a concentrated single-stock position, and the diversification math almost always outranks the tax math. Vanguard’s How America Saves 2026 found that only 2% of participants hold a concentrated position of more than 20% in company stock, down from 6% in 2016 — the industry has spent a decade talking people out of exactly this exposure.

Your state. State income tax applies to both the ordinary income on the basis and the capital gain on the NUA. Because it hits the upfront bill harder than the deferred one, a high state rate pulls the crossover closer and makes NUA less attractive — the mirror image of the state-tax logic in our asset location strategy breakdown.

Your age. Older is better for NUA. Required minimum distributions eventually force money out of the rollover IRA at ordinary rates, which caps how long the deferral advantage can run. A 70-year-old has a much shorter runway for the rollover to catch up than a 55-year-old does.

What barely matters: the exact size of the position, and whether the stock has doubled or gone up 900%. Those change the dollars, not the decision.

Four Traps That Disqualify the Election Before You Get to the Math

The NUA rules are unforgiving in a way most tax provisions aren’t. Miss a requirement and the opportunity is gone, sometimes permanently.

1. The distribution must be a true lump sum. The entire plan balance has to leave in a single tax year — not just the stock. Your year-end balance must read zero. You can roll the non-stock portion to an IRA; you just can’t leave a dollar behind.
2. A prior distribution in the same year kills it. If you took any distribution — even a small one, and in some readings even a plan loan — after your triggering event but before the lump sum, the year is spent. Kitces documents a case where a $10,000 retirement-celebration withdrawal cost a retiree the election on $400,000 of stock until she reached 59½ and got a fresh triggering event.
3. The shares must move in kind. Selling inside the plan and wiring cash to a brokerage account doesn’t qualify. The certificates have to transfer.
4. Selling and rebuying inside the plan resets your basis. A participant who panic-sold company stock in a drawdown and bought back in at a higher price permanently overwrote a low basis — and with it, the reason NUA existed for them. If you think you’ll ever use this, treat the basis as an asset worth protecting.

One more mechanical note: if you’re under 59½ and don’t qualify for the age-55 separation-from-service exception, the 10% early withdrawal penalty applies — but only to the basis, not the full value. On a $650,000 position with a $45,000 basis, that’s $4,500, or 0.7% of the position. Small enough that it rarely changes the answer. Whether the shares stay in a plan or move to an IRA is a separate question from how they move, and our walkthrough of 401(k) rollover options when you change jobs covers the four standard paths if you decide NUA isn’t for you.

A Note From Chris

I’ve never had employer stock in a plan — I’m a software engineer who has kept his retirement money in boring index funds since the beginning, and the couple of times a company offered a stock purchase plan I took the discount and sold immediately. So I came at this the way I come at most tax strategies: skeptical, and curious about whether the spreadsheet agrees with the enthusiasm.

It mostly doesn’t. When I built the crossover model for this post, what surprised me was how fast the rollover catches up — five to nine years across the whole basis range, not the twenty-plus I expected from how confidently NUA gets recommended. The behavioral economics angle is interesting too: paying $65,600 in tax today to save a hypothetical amount later is exactly the kind of trade our brains are bad at evaluating, and the fact that the immediate cost is so vivid probably explains why people either dismiss NUA outright or over-commit to it. The honest version is narrower than either. It’s a good move for a specific person — low basis, high future bracket, near or past retirement age, needs taxable liquidity — and a quietly expensive one for everybody else. Worth noting: if your other income is low enough that the gain fits in the 0% long-term bracket, the arithmetic changes completely, which is the same logic behind capital gains harvesting in the 0% bracket.

Frequently Asked Questions

Does net unrealized appreciation apply to stock in a Roth 401(k)?
No meaningful benefit. Qualified Roth 401(k) distributions come out tax-free already, so there’s no ordinary-income problem for the NUA rules to solve. The election is designed for pre-tax plan assets.

Do NUA shares get a step-up in basis when I die?
No. Under Revenue Ruling 75-125, the NUA portion is treated as income in respect of a decedent and does not receive a step-up. Your heirs will owe long-term capital gains tax on that embedded gain when they sell. Appreciation that occurs after the distribution date is a separate matter and does step up.

Can I do NUA on only some of my shares?
Often yes, but it depends on your plan. The regulations permit cherry-picking specific low-basis lots for in-kind distribution while rolling the rest to an IRA. Many plan administrators don’t track lot-level basis and use an average instead, which removes the option. Confirm with the administrator before building a strategy around it — the answer determines whether you’re working with your best basis or your blended one.

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Written by Chris Steve

Chris Steve is a software engineer with a deep interest in personal finance, behavioral economics, and AI. He started Money & Planet to share clear, research-backed money guides — the kind that explain the math instead of pushing products. His writing focuses on long-term wealth building, the psychology behind spending and investing decisions, and the practical tools regular people can use to make smarter financial choices.