Net Unrealized Appreciation (NUA) from 401(k) Employer Stock at Retirement

Net Unrealized Appreciation is a carve-out in IRC §402(e)(4) that most retirees never hear about until they’ve already done the rollover and lost it. If your 401(k) holds employer stock, meaning shares of the company you worked for, inside the qualified plan, you have a one-time election at separation to take those shares in-kind, pay ordinary income tax on the cost basis only, and hold the appreciation as long-term capital gains forever.

The effect is significant. A retiree with $400,000 of employer stock in a 401(k), bought at an average basis of $60,000, would owe ordinary income tax on $400,000 if they rolled the whole plan to an IRA. Under NUA, they owe ordinary income tax on $60,000 and long-term capital gains tax on the $340,000 appreciation when sold. At federal rates, that swing is roughly $70,000 in tax savings before state.

The catch is that NUA requires a specific distribution pattern and an inflexible timing window. Miss the window, and the election is gone.

What qualifies as employer stock

The stock has to be stock of the employer who sponsors the plan (or a parent/subsidiary). Mutual funds holding the stock don’t qualify. ESOP accounts, employer-stock funds inside a 401(k), and directly-held employer shares inside the plan all qualify.

Tech companies with strong stock performance, think the FAANG cohort, Microsoft, Oracle, Tesla, often have employees with substantial employer-stock concentrations inside their 401(k)s because of employer match in company stock or voluntary employee allocations. These are the accounts where NUA matters.

The four conditions for a qualifying lump-sum distribution

IRC §402(e)(4)(D) requires all four of these to be true in a single calendar year:

The entire balance of the 401(k) must be distributed
The distribution must happen in one tax year
The distribution must follow a triggering event: separation from service, reaching age 59½, death, or disability
The employer stock portion must be distributed in-kind (as shares, not cash)

The cash portion of the plan, bond funds, target-date funds, other equity funds, gets rolled to an IRA as usual. Only the employer stock comes out in-kind to a taxable brokerage account.

If you take any partial distribution before the qualifying lump-sum, you blow the election. That includes taking a required minimum distribution or doing a partial rollover. The plan has to empty in one pass.

How the tax is structured

At the moment you receive the employer stock in-kind:

You owe ordinary income tax on the cost basis (what the plan originally paid for the shares)
If you’re under 55 at separation, there’s also a 10% early-distribution penalty on the basis (not on NUA)
The appreciation, NUA, is not taxed at distribution

When you later sell the shares:

NUA is always long-term capital gains, regardless of how long you hold after distribution
Any further appreciation after distribution follows normal capital gains holding-period rules

This is what makes NUA powerful. You’re converting what would have been ordinary income (withdrawn from an IRA at your marginal rate, potentially 37% federal plus state) into long-term capital gains (20% federal max, plus 3.8% NIIT, plus state).

When NUA doesn’t make sense

Three scenarios kill the math:

Low appreciation ratio. If the stock is worth $200,000 and the basis is $180,000, you’d pay ordinary tax on $180,000 to save capital-gains-rate tax on $20,000. The juice isn’t worth the squeeze. A rough rule of thumb: the appreciation should be at least 2-3x the basis for NUA to win.

Early retirement with the 10% penalty. If you separate at 52 and take employer stock in-kind, the basis amount triggers the 10% early-withdrawal penalty under IRC §72(t). This can erase the benefit unless appreciation is very high.

IRMAA and AGI-linked surcharges. The basis amount hits your AGI in the distribution year, which can push Medicare Part B and Part D IRMAA surcharges two years later. For a retiree at 63, the basis income could lift IRMAA tiers at 65. Model the Part B/D surcharges before committing.

The charity angle

One refinement: donate the NUA shares to a donor-advised fund after distribution. You get a charitable deduction at fair market value (up to 30% of AGI for appreciated stock under IRC §170(b)(1)(C)(ii)), avoid the capital gains tax on NUA entirely, and still paid only the basis-level ordinary income at distribution.

For philanthropically-inclined retirees with employer-stock concentrations, this combination, NUA distribution followed by partial DAF donation, is one of the highest-efficiency moves available.

Timing around the calendar year

The lump-sum has to complete in one tax year. Plans sometimes take 4-8 weeks to process in-kind distributions. If your separation is in October and you’re aiming for a same-year distribution, start the paperwork in September. If it’s in November, consider waiting until January and retiring effective January 1, because a late-December partial processing can kill the election.

If the plan has outstanding loans, they’re typically distributed as an offset, which counts as part of the lump-sum. Check with the plan administrator.

What happens if you rollover first and regret it

Once employer stock is rolled to an IRA, it’s treated as ordinary IRA assets. The NUA election is lost permanently. There’s no do-over in a later tax year. You cannot distribute from the IRA back into a 401(k) to rebuild the election.

This is the single most common mistake: a retiree sets up a rollover through a consolidation-happy advisor, the employer stock goes to the IRA along with everything else, and the NUA opportunity evaporates. The plan’s lump-sum paperwork has a specific election box for NUA treatment. Check it.

Frequently asked

Does NUA apply to stock I bought through the ESPP outside the 401(k)? No. NUA is specific to IRC §402(e)(4) and applies only to employer securities held inside a qualified plan. ESPP stock held in a brokerage account is already in after-tax form and doesn’t need the election.

What if I have both pre-tax and after-tax money in the 401(k)? After-tax contributions (including mega-backdoor after-tax) can be rolled to a Roth IRA while the pre-tax portion and employer stock are distributed under the lump-sum. The plan administrator can split these when you request the distribution.

Can I do NUA on shares inside a Roth 401(k)? No. Roth 401(k) distributions are already tax-free on qualifying distributions. NUA only applies to pre-tax employer stock.

How does NUA interact with state income tax? Most states tax the basis as ordinary income and the NUA as capital gains, mirroring federal treatment. A few states, notably Pennsylvania, have different rules. If you’re moving states around retirement, the NUA election’s tax impact depends heavily on which state you’re residing in at distribution.

What’s the §6501 statute of limitations concern? None specific to NUA itself, but the three-year assessment period under §6501 starts when you file the return claiming NUA. Keep the plan’s cost basis statement permanently, the IRS can request substantiation years later when you eventually sell.