Rolling over a 401(k): the decision most people make too fast

The four options, honestly described

Leave it where it is. Plans generally must let you stay if the balance exceeds a small threshold. You keep ERISA creditor protection, institutional pricing, and — if you separated in or after the year you turned 55 — penalty-free access. You give up flexibility, you deal with a former employer's administrator, and you accumulate accounts across a career until nobody, including you, knows where they all are.

Roll it to the new employer's plan. Consolidates, preserves plan-level protections, and keeps the door open for backdoor Roth contributions. It also puts you in a menu you did not choose, and the new plan must accept incoming rollovers, which not all do.

Roll it to an IRA. Unlimited investment selection, one account, full control of distributions and beneficiaries, no administrator between you and your money. Often the right answer. It also forfeits the age-55 rule, changes creditor protection, can block a backdoor Roth through the pro-rata rule, and permanently ends the possibility of NUA treatment for employer stock.

Cash it out. The entire pre-tax balance becomes ordinary income, 20% is withheld immediately, and a 10% additional tax generally applies under 59½. It is the most expensive option available, and a meaningful share of departing employees take it anyway.

Creditor protection is not the same in both places

Employer plans covered by ERISA hold assets under an anti-alienation provision that gives them broad protection from creditors — about as strong as anything on the personal balance sheet.

IRAs are protected differently. In bankruptcy, federal law exempts traditional and Roth IRA contributions and earnings up to an inflation-adjusted cap — currently $1,711,975, effective April 1, 2025, and reviewed every three years. Amounts rolled over from an employer plan are generally exempt without regard to that cap. Outside bankruptcy, IRA protection is a matter of state law and varies substantially; Pennsylvania and New Jersey have their own statutes with their own conditions.

For most people the difference is theoretical. For physicians, business owners with personal guarantees, board members, and anyone with meaningful professional liability exposure, it is not, and it belongs in the analysis before the rollover paperwork gets signed.

Fees and menus cut both ways

The reflexive claim is that IRAs are cheaper. That is often false.

Large 401(k) plans buy institutional share classes and separate accounts at pricing genuinely unavailable to retail investors. Some also hold a stable value fund with a credited rate no money market or short bond fund can match. Neither travels to an IRA. Small plans, on the other hand, can be expensive — recordkeeping fees, per-participant charges, and retail-priced menus with revenue sharing baked in. Those are worth leaving.

The honest version is that the comparison requires reading the plan's fee disclosure against a specific IRA implementation. That takes an afternoon. It is done far less often than the confidence of the usual advice would suggest.

The age-55 rule of separation, which a rollover destroys

Distributions from a 401(k) are generally exempt from the 10% additional tax if you separate from service during or after the calendar year you turn 55. For qualified public safety employees, the age is 50.

The exception applies only to the plan of the employer you separated from. It does not apply to IRAs. Roll the balance to an IRA and it is gone — you are back to waiting until 59½ or using a substantially equal periodic payment arrangement, which is rigid and unforgiving.

The failure mode is specific. Someone retires at 56, rolls everything to an IRA on general principle, then needs income before 59½ and no longer has a penalty-free path to it. Leaving enough in the plan to cover the years before 59½ and rolling the rest is a version of this decision people frequently do not know is available.

The rule keys off the year of separation, not the age at which you take the distribution. Separating at 53 and waiting until 56 does not qualify.

RMD aggregation works differently

Once required minimum distributions begin — currently at 73 — the mechanics differ by account type.

IRA RMDs are calculated separately for each IRA but can be taken from any one of them in total. That lets you satisfy the whole obligation from one account and leave others untouched, which matters if one holds an illiquid position or an annuity.

401(k) RMDs must be calculated and taken separately from each plan. Someone with three old 401(k)s has three separate obligations, each satisfied from its own account. Missing one is a common and avoidable error.

There is also the still-working exception: if you are still employed at 73 and do not own more than 5% of the company, you can generally defer RMDs from that employer's plan until you retire. No such exception exists for IRAs, and it can be a genuine reason to roll old balances into a current plan rather than out.

The backdoor Roth conflict

If you earn too much for a direct Roth IRA contribution and use the backdoor strategy — a nondeductible traditional IRA contribution converted to Roth — a large rollover IRA breaks it. The pro-rata rule aggregates all traditional, SEP and SIMPLE IRA balances at December 31 and taxes conversions proportionally. A seven-figure rollover IRA means a backdoor conversion is almost entirely taxable.

This runs directly against the standard advice. For a high earner who values annual Roth contributions, rolling into the new employer's plan rather than into an IRA preserves the backdoor. It is one of the clearest cases where the default answer is the wrong one, and it turns on a rule most people have never heard of.

Direct versus indirect, and the 20% trap

A direct rollover goes trustee to trustee. Nothing is withheld, nothing is reportable as income, and there is no deadline to miss. This is the version to ask for by name.

A 60-day indirect rollover pays the money to you, and you have 60 days to redeposit it. Two problems make this worse than it sounds.

First, a plan distribution paid to you is subject to mandatory 20% withholding — even if you tell the administrator you intend to roll it over. There is no waiver. On a $500,000 distribution, $100,000 goes to the Treasury and $400,000 arrives in your account.

Second, to complete a full rollover you must deposit the entire $500,000 within 60 days. The missing $100,000 has to come from your own pocket, and you wait until filing to recover it. Deposit only the $400,000 you received and the $100,000 becomes a taxable distribution, plus a 10% additional tax if you are under 59½ and no exception applies.

The IRS can waive the 60-day requirement in limited circumstances beyond your control, and there is a self-certification procedure for certain situations. Neither is a plan.

The once-per-year rollover rule

You may make only one IRA-to-IRA 60-day rollover in any 12-month period, and the limit applies across all your IRAs in aggregate — not per account. This has been the rule since 2015. A second one in the same window is not a rollover; it is a distribution, and it can be an excess contribution in the receiving account on top of that.

The limit does not cover trustee-to-trustee transfers, Roth conversions, plan-to-IRA rollovers, IRA-to-plan rollovers, or plan-to-plan rollovers. All are unlimited. Which is the practical takeaway — use direct trustee-to-trustee movement and the rule never applies to you.

Net unrealized appreciation

If your 401(k) holds employer stock — common for anyone who spent a career at a public company, and especially common in plans with a company stock match — there is a provision worth understanding before the rollover paperwork is signed. Once the stock is rolled into an IRA, this option is gone permanently.

What NUA is

Net unrealized appreciation is the growth in employer stock that occurred inside the plan: market value at distribution minus the plan's cost basis in the shares.

Ordinarily, everything that comes out of a 401(k) is ordinary income. NUA is the exception. Distribute employer stock in kind to a taxable brokerage account and the tax splits in two:

• The cost basis is ordinary income in the year of distribution, taxable immediately at your marginal rate.
• The appreciation is not taxed at distribution at all. It is taxed as long-term capital gain when you sell — automatically long-term regardless of how long the shares were held inside the plan, and regardless of how long you hold them afterward.

Someone with $900,000 of employer stock and a $90,000 basis pays ordinary income tax on $90,000 now and long-term capital gain rates on $810,000 later, on their own timing. Roll the same position into an IRA and all $900,000 eventually comes out as ordinary income, on the IRS's timing once RMDs begin.

Two additional features. The NUA portion is generally not subject to the 3.8% net investment income tax. And if you are under 59½, the 10% additional tax applies only to the basis amount — which, on a low-basis position, is a small number relative to the value distributed.

The qualifying conditions, all of which are required

A triggering event. Separation from service, reaching age 59½, total and permanent disability (for self-employed participants), or death. The triggering event must precede the distribution.

A lump-sum distribution. The entire balance of the plan — and of all like plans of that employer — must be distributed within a single tax year. Not just the stock. Everything. The non-stock assets can be rolled to an IRA in the same year, which is the normal approach. What is not fine is leaving a residual balance in the plan at December 31. A stray dividend posting after the account was emptied, or a partial distribution taken earlier in the same year for an unrelated reason, can disqualify the whole thing.

In-kind distribution of the shares. The actual shares must move to a taxable brokerage account. Selling inside the plan and buying the same stock outside does not qualify, and neither do phantom shares or options. Unitized company stock funds usually qualify if the units convert to transferable shares — a question for the administrator.

It is irreversible, and it is mutually exclusive with a full rollover

Once the stock is distributed and the election is made, it cannot be undone. The mirror is equally permanent: once the shares are rolled into an IRA, NUA treatment is gone and cannot be recovered. There is no correction window in either direction, and you cannot do both — NUA and rolling everything to an IRA are alternatives, not a sequence.

This is why the rollover conversation and the NUA conversation have to happen at the same time, before anything moves. In practice they usually happen in the wrong order, and the second one is academic by the time it starts.

When the math favors it, and when it does not

NUA is a trade: ordinary income tax now on the basis, in exchange for capital gain treatment later on the appreciation. Three variables decide it.

Basis as a percentage of value. The dominant factor. A position with 10% basis is a strong candidate. A position with 60% basis usually is not — you would be paying substantial ordinary income tax today to preserve deferral you already had for free. There is no universal threshold, but the case weakens quickly as basis rises, and analyses commonly find the rollover winning once basis exceeds roughly 40 to 50 cents on the dollar.

The bracket differential. The benefit is the spread between your ordinary rate on the basis and your capital gain rate on the appreciation. A large distribution can push the basis into higher ordinary brackets and simultaneously push the gain into the 20% capital gain bracket, compressing the spread it was meant to capture. State tax matters too — states that tax capital gains as ordinary income remove one side of the arbitrage entirely.

Time horizon. Money left in an IRA keeps compounding tax-deferred. Money paid in tax today does not. The longer the horizon, the more the deferral is worth and the more likely a rollover overtakes NUA. The strategy generally suits participants closer to retirement rather than further from it.

Two more points get missed. NUA is income in respect of a decedent — it does not receive a step-up in basis at death, unlike ordinary appreciated securities. And NUA rewards holding a concentrated position, which is a portfolio decision dressed as a tax decision. A tax-optimized route into a single stock that represents a large share of net worth is still a single stock, and whether that risk is worth the tax benefit is the question the tax analysis does not answer.

Many plans also do not permit selecting specific share lots, applying average cost across all shares instead. That administrative detail alone can eliminate the strategy's main advantage, and it is worth confirming before any modeling begins.

What to gather, and who to coordinate with

Assemble: your most recent plan statement with the cost basis of employer stock shown separately — request it explicitly if it is not there; the summary plan description covering distributions, in-kind distributions and incoming rollovers; your separation date and the year you turned 55; the plan's fee disclosure; balances of all traditional, SEP and SIMPLE IRAs; the new employer's plan menu and whether it accepts rollovers; and any outstanding plan loan, which typically becomes a deemed distribution on separation if not repaid.

Coordinate with the plan administrator on lump-sum mechanics and whether share lots can be selected — in writing. Coordinate with your CPA on modeling the NUA election against a full rollover across a realistic holding period, including state tax, and on Form 1099-R box 6 reporting. Coordinate with your advisor on the concentration question and on the sequence of moves within a single tax year, because the lump-sum requirement is unforgiving about timing. If creditor exposure is a live concern, coordinate with counsel before the balance leaves the plan rather than after.

This article is educational and is not tax, legal, or investment advice. Individual circumstances differ, and the rules change.