What to Do With Your 401(k) After Leaving a Job: The Four Doors, Ranked

When you leave a job, your 401(k) has four doors: leave it in the old plan, roll it into the new employer's plan, roll it into an IRA, or cash it out. Ranked by how often each is the right move, a rollover into a good new-employer plan or staying in a good old one comes first, an IRA rollover comes next and is the right call when the plans are expensive and you are not planning a backdoor Roth, and cashing out comes last because it costs income tax, a 10% penalty before age 59½, and decades of growth. None of the first three doors triggers tax if you move the money directly.

The four doors, compared

Door 1: leave it where it is

Doing nothing is a legitimate choice as long as the balance is above the plan's small-balance threshold, which the plan sets within a limit federal law allows, currently a few thousand dollars. Below it, the plan may cash you out (for very small balances) or roll the money into an IRA in your name without asking, often into a cash-like holding. Above it, the money stays invested under the old plan's rules: the same funds, often at institutional share-class prices cheaper than a retail account, with full federal creditor protection, and with the rule of 55 intact if you left that employer in or after the year you turned 55.

The costs are administrative rather than financial. Some plans charge former employees a quarterly fee or restrict partial withdrawals to one a year. You cannot contribute, the employer can change or merge the plan, and the account is one more login to lose track of over a career of several jobs. Keep the beneficiary designation current, and read the statement once a year for fee changes.

Door 2: roll it into the new employer's plan

Most plans accept incoming rollovers once you are eligible to participate. The case for this door is consolidation plus everything a 401(k) protects that an IRA does not: unlimited federal protection from most creditors, the rule of 55 at the new employer if you leave it at 55 or older, the ability to borrow against the balance if the plan allows loans, and a later exception that lets you delay required distributions from a current employer's plan while you are still working. It also keeps pre-tax money out of your IRAs, which matters if you ever make backdoor Roth contributions, for the reason in the next door.

The case against is the new plan's menu. Compare expense ratios on the index funds you would actually hold; a plan whose cheapest stock index fund costs 0.60% a year is expensive next to one at 0.05%, and over 25 years on a $100,000 balance that difference is worth tens of thousands of dollars. The investment fee calculator shows the exact gap for your numbers. Ask for a trustee-to-trustee transfer so the money never sits as a check in your mailbox.

Door 3: roll it into an IRA

A rollover into a traditional IRA at a brokerage you choose opens the whole market: any index fund, any expense ratio, one account that collects every old plan. For someone with three former employers and three mediocre fund menus, this is the door that makes the retirement picture legible. The money arrives as cash and has to be invested; a surprising amount of rolled money sits in a settlement fund for years because nobody placed the trade.

Two doors close behind you. First, the pro-rata rule. A backdoor Roth works by making a nondeductible IRA contribution and converting it, and the conversion is tax-free only if you hold no other pre-tax IRA money. Roll $95,000 of pre-tax 401(k) money into an IRA and then convert a $6,000 nondeductible contribution, and roughly 94% of the conversion becomes taxable, because the IRS treats all your IRAs as one pot. The backdoor Roth guide covers the mechanics; the short version is that anyone above the Roth IRA income limit should keep pre-tax money in a 401(k). Second, the rule of 55 does not exist for IRAs. Money you might need between 55 and 59½ belongs in a 401(k), not an IRA. IRAs do have their own penalty exceptions, including a limited one for a first home and one for higher education, that 401(k)s lack, and creditor protection for IRAs is capped in bankruptcy and set by state law outside it.

Door 4: cash it out, with the math on $25,000

Take a 38-year-old with a $25,000 pre-tax balance who asks for a check. The plan is required to withhold 20% for federal tax, so the check is $20,000. That withholding is a deposit, not the bill. At filing, the $25,000 is ordinary income: at an illustrative 22% federal marginal rate that is $5,500, the 10% early-withdrawal penalty adds $2,500, and a 5% state income tax adds $1,250. Total cost: $9,250, leaving $15,750 of the original $25,000. Since $5,000 was withheld, another $4,250 is due with the return, in a year when unemployment benefits or severance may already have pushed income up.

The fourth cost is the one the statement never shows. The same $25,000 left invested at an assumed 6% annual return for 30 years grows to roughly $144,000. The 401(k) early withdrawal calculator runs your balance, rate, and state, and the early withdrawal guide covers the penalty exceptions, including the rule of 55 and hardship rules. If a genuine emergency requires some of the money, take only that amount and roll the rest; the plan will split the distribution, and a partial cash-out does not require cashing out the whole balance.

Direct vs. indirect rollover: the 60-day clock and the withholding trap

A direct rollover moves the money from the old plan to the new custodian without passing through you. The check, if there is one, is made out to the new custodian for your benefit, or the money is wired. Nothing is withheld, nothing is taxed, and there is no deadline. This is the default to request every time.

An indirect rollover is a check made out to you. The plan must withhold 20% for federal tax, and you then have 60 calendar days from receipt to deposit the full pre-withholding amount into an IRA or new plan. On a $50,000 balance the check is $40,000, and completing the rollover means depositing $50,000, with the missing $10,000 coming from your own savings. You recover the withheld $10,000 as a credit when you file, months later. Deposit only the $40,000 and the $10,000 counts as a distribution: taxed, and penalized if you are under 59½. Miss the 60 days and the whole amount is a distribution. There is a self-certification process for certain excuses such as a lost check or a custodian error, but it is a rescue, not a plan. Indirect rollovers between IRAs are also limited to one per 12 months across all your IRAs; plan-to-IRA rollovers are not subject to that limit, but there is no reason to test it.

Loose ends: the plan loan, Roth money, employer stock, and vesting

An outstanding plan loan

A 401(k) loan is repaid through payroll, and separation ends payroll. Most plans make the balance due within a short period after you leave. If it is not repaid, the plan offsets your balance by the unpaid amount and reports it as a distribution. You then have until the tax-filing deadline for that year, including extensions, to deposit the same amount into an IRA or new plan from your own money; if you do, the offset becomes a rollover and no tax is due. An $8,000 unpaid loan therefore needs an $8,000 deposit by that deadline, or it is taxed and, under 59½, penalized. Put this on the day-one list, ahead of any rollover decision.

Roth 401(k) money

Roth 401(k) balances roll to a Roth IRA or to a new plan's Roth account, never to a traditional IRA. One timing detail: a Roth IRA's five-year clock runs from the first year you funded any Roth IRA, not from your Roth 401(k) start date, so if you have never opened a Roth IRA, opening one now starts that clock before you need it. Pre-tax money can also go directly into a Roth IRA, but that is a conversion and the whole amount is taxable in the year you do it.

Employer stock

If the plan holds shares of your former employer that have appreciated a lot, a rule called net unrealized appreciation can let you move the shares to a taxable account and pay long-term capital gains rates on the growth instead of ordinary income rates later. Rolling those shares into an IRA forfeits that treatment permanently. The rules are specific about how the distribution must be taken, so this is a stop-and-ask-a-professional flag before you sign any rollover form.

Vesting

Your own contributions and their growth are always yours. Employer contributions are yours only to the extent they have vested, and leaving forfeits the unvested portion. Check the vested balance on the statement rather than the headline; if a vesting date falls a few weeks after your separation date, that date is something to raise in the severance conversation, because moving it can be worth thousands.

A decision flow

1. Is there an outstanding plan loan? Handle it first: repay it, or plan to deposit the offset amount by the filing deadline.
2. Is the balance below the plan's force-out threshold? Move it before the plan moves it for you.
3. Does the plan hold appreciated employer stock? Talk to a tax professional before any rollover.
4. Do you make, or expect to make, backdoor Roth contributions? Keep the pre-tax money in a 401(k): leave it or roll it to the new plan, not to an IRA.
5. Are you 55 or older, or will you be when you next leave a job, and might you need the money before 59½? Prefer a 401(k) for the same reason.
6. Otherwise, compare the fund menus and expense ratios of the old plan, the new plan, and an IRA; the cheapest good menu wins, and having fewer accounts is the tiebreaker.
7. Cash out only what no other source can cover, and roll the rest.

The 401(k) calculator shows what the balance becomes under each door at your contribution rate and horizon, and the rest of the post-layoff sequence, from the unemployment claim to the survival budget, is in money after a layoff and the wider money after a layoff collection.

An old 401(k) is the account most likely to be forgotten, and the one most likely to be raided in a bad month. Stoia keeps every retirement account, old and new, next to the emergency fund and the card balance in one live picture, launching 2026, so the door you choose is the one the whole balance sheet supports.