Net Unrealized Appreciation (NUA) 401(k) Guide 2026: How the Tax Break Works

What Is Net Unrealized Appreciation (NUA)?

Net Unrealized Appreciation (NUA) is a special tax rule, described in IRS Publication 575, that applies when your 401(k) holds employer company stock. Normally, rolling a 401(k) into a Traditional IRA defers all tax until withdrawal, at which point every dollar — including any growth — is taxed as ordinary income (up to 37% federally in 2026). The NUA strategy takes a different path for the employer-stock portion: instead of rolling that stock into an IRA, you distribute it in-kind directly to a taxable brokerage account. You pay ordinary income tax immediately, but only on the stock's original cost basis (what the plan actually paid for it). The appreciation above that cost basis — the NUA itself — is taxed at long-term capital gains rates (0%, 15%, or 20% federally) whenever you eventually sell, regardless of how long you've personally held the shares since distribution.

This guide covers exactly how NUA works, who is eligible, the tax math with a worked example, and the key risks of using this strategy instead of a standard IRA rollover.

Why Would You Choose NUA Over a Standard IRA Rollover?

A standard 401(k)-to-IRA rollover defers all tax until withdrawal, at which point 100% of the distribution — original contributions, employer match, and all investment growth — is taxed as ordinary income, up to the top 37% federal bracket in 2026. For an employee holding heavily appreciated employer stock inside a 401(k), that means potentially decades of capital appreciation eventually getting taxed at ordinary income rates instead of the lower capital gains rates that would apply to the same stock held in a regular taxable brokerage account.

NUA breaks that appreciation out of the ordinary-income box. By taking the employer stock as an in-kind distribution rather than rolling it into an IRA, only the original cost basis is taxed as ordinary income up front. The (often much larger) appreciation is taxed later, at sale, at the lower long-term capital gains rate — and that lower-rate treatment applies no matter how briefly you've personally held the shares after distribution, because NUA specifically exempts this appreciation from the usual holding-period test.

The strategy is most valuable for long-tenured employees at publicly traded companies who accumulated employer stock inside their 401(k) over many years (through direct stock purchase options, employer matching in stock, or profit-sharing contributions in stock) and where that stock has appreciated substantially above its original cost.

What Counts as a Qualifying Triggering Event?

NUA treatment is only available following a specific "triggering event," consistent with IRS guidance on lump-sum distributions from qualified plans:

• Separation from service — leaving the employer that sponsors the plan (does not apply to self-employed individuals in their own plan)
• Reaching age 59½ — even while still employed, if the plan allows an in-service distribution at this age
• Death — distribution to a beneficiary or the estate
• Disability — for self-employed individuals specifically

Simply wanting to move money out of a 401(k) is not enough — one of these specific events must have occurred, and the distribution must otherwise qualify as a lump-sum distribution under the rules that also govern Form 4972 (Tax on Lump-Sum Distributions).

Why Does the Entire Plan Balance Need to Be Distributed?

NUA's favorable tax treatment is only available as part of a qualifying lump-sum distribution — the entire vested balance of all the employer's qualified plans of that type must be distributed within a single tax year. This is a hard requirement, not a preference: distributing employer stock while leaving other 401(k) assets behind in the plan, or spreading the distribution across multiple tax years, disqualifies the transaction from NUA treatment entirely.

In practice, this means you must decide, in the same tax year, what happens to every dollar in the plan — not just the employer stock. The typical structure is: take the employer stock as an in-kind distribution to a taxable brokerage account (to capture NUA treatment), and simultaneously roll the remaining non-stock balance into a Traditional IRA (a normal, non-taxable rollover, since that portion isn't part of the NUA transaction). Getting this sequencing and documentation right typically requires coordination with the plan administrator and a tax professional — a small mistake (like accidentally rolling a portion of the stock into the IRA instead of distributing it in-kind) can permanently disqualify the NUA election for those shares.

Worked Example: NUA vs Full IRA Rollover

Scenario: An employee separates from service at age 55 with $400,000 of employer stock inside their 401(k). The plan's original cost basis in that stock is $100,000; the stock has appreciated to a current fair market value of $400,000 — a Net Unrealized Appreciation of $300,000. Assume a 24% marginal ordinary income tax bracket and a 15% long-term capital gains rate, and that the employee sells the stock the year after distribution (satisfying the standard 1-year long-term holding period on any post-distribution growth, which we'll assume is zero for simplicity).

In this simplified example, the NUA strategy saves roughly $27,000 in federal tax on the same $400,000 of employer stock, because $300,000 of the value is taxed at the 15% capital gains rate instead of the 24% ordinary income rate. The larger the appreciation relative to cost basis, and the bigger the gap between your ordinary income bracket and the capital gains rate, the more valuable NUA becomes. Note this example ignores the 3.8% Net Investment Income Tax, which could apply to the capital gain portion for high-MAGI taxpayers, and any state income tax, which varies by state and generally applies to both the ordinary-income and capital-gains portions.

What Are the Key Risks of Using NUA?

• You lose the IRA's ordinary-income deferral entirely on the stock portion. The cost-basis tax bill is due immediately in the distribution year, in cash, even though the stock itself hasn't been sold yet — this can create a liquidity crunch if you don't have other funds to pay the tax.
• Concentration risk. Holding a large position in a single company's stock in a taxable account (rather than diversifying inside an IRA) exposes you to the risk of that one stock declining sharply before you sell.
• Early withdrawal penalty exposure. If you're under 59½ at the time of distribution and no exception applies, the ordinary-income cost-basis portion can still be subject to the standard 10% early withdrawal penalty, in addition to ordinary income tax.
• Irrevocable, all-or-nothing timing. Because NUA requires distributing the entire plan balance within one tax year, you can't "undo" the decision later or spread it across years the way you could with a series of partial IRA withdrawals or Roth conversions.
• Estate planning trade-off. Assets left in a Traditional IRA get different treatment for beneficiaries than NUA stock held in a taxable account; heirs inheriting NUA stock generally do not get a full step-up in basis on the NUA portion the way they would with most other inherited taxable assets, since the NUA portion retains its original built-in gain character. This is a complex, plan- and estate-specific detail that should be reviewed with a CPA or estate attorney.
• Complexity and administrative risk. A single misstep in coordinating the in-kind stock distribution with the rollover of the remaining balance can disqualify the entire NUA election, so this strategy is rarely a do-it-yourself project.

How Does NUA Compare to a Regular 401(k) Rollover?