9 Things Almost Every Retiree Gets Wrong When Rolling Over Their 401(k)

Rolling over a 401(k) feels like a simple task: move the money, pick the account, done. But the mechanics are more specific than most people realize, and the mistakes are expensive. A single misstep might trigger an unexpected tax bill or leave your money sitting uninvested for years, sabotaging your financial fitness during retirement.

Here are the most common rollover mistakes retirees make and how to avoid them.

Leaving your rollover sitting in cash

A rollover isn't complete until the money is invested. Vanguard found that 28% of investors who rolled money into an IRA in 2015 still had it sitting in cash seven years later.

Because IRAs don't automatically invest like many 401(k) plans, Vanguard estimates this oversight costs savers $172 billion annually in missed growth. For investors under age 55, it can also reduce retirement savings by about $130,000 per person by retirement age.

Choosing an indirect rollover over a direct rollover

An indirect rollover sends the money to you instead of directly to your new retirement account. The IRS requires 20% to be withheld for taxes, so a $20,000 rollover arrives as a $16,000 check. You then have 60 days to deposit the full $20,000, or the missing amount becomes taxable and may also trigger a 10% early withdrawal penalty.

Missing the 60-day rollover deadline

If you choose an indirect rollover and miss the 60-day window to complete the deposit, the IRS treats the entire amount as a taxable distribution. On a $20,000 distribution in the 22% bracket, that's $4,400 in federal taxes. If you're under 59½, add a 10% penalty — another $2,000. The IRS does allow for hardship waivers in limited circumstances, but missing the deadline due to simple delay doesn't qualify.

Accidentally rolling pretax 401(k) money into a Roth IRA

Rolling pretax 401(k) dollars directly into a Roth IRA is a taxable conversion, not a tax-free rollover. Every dollar transferred is treated as ordinary income in the year of the rollover

On a $50,000 accidental conversion in the 22% bracket, that's an unexpected $11,000 federal tax bill. If the conversion also pushes income over an IRMAA threshold, Medicare premiums rise two years later.

Doing more than one IRA rollover in 12 months

The IRS once-per-year rollover rule prohibits doing more than one IRA-to-IRA rollover within a 12-month period. Violating it turns the second rollover into a taxable distribution and generates a 6% excess contribution penalty per year until the error is corrected.

The rule applies per person across all IRAs combined, not per account. Direct trustee-to-trustee transfers are not subject to this limit and are the safest way to move IRA money.

Ignoring the Rule of 55 before rolling over your 401(k)

The IRS Rule of 55 allows penalty-free withdrawals from a 401(k) if you leave your employer in or after the year you turn 55. That exemption disappears the moment the money moves to an IRA, where the penalty-free withdrawal age is 59 1/2. A retiree who plans to access funds between 55 and 59½ and rolls over their 401(k) into an IRA loses the penalty-free access entirely.

Rolling over employer stock without considering NUA

If your 401(k) includes highly appreciated employer stock, rolling everything into an IRA may increase your future tax bill.

Using Net Unrealized Appreciation (NUA) instead allows the stock to move into a taxable brokerage account. You pay ordinary income tax only on its original cost basis, while future gains qualify for lower long-term capital gains tax rates when the shares are sold.

Not consolidating multiple old 401(k) accounts

Leaving old 401(k) accounts with different employers makes retirement savings harder to manage. Consolidating them into a single IRA simplifies investing, reduces paperwork, and makes it easier to track performance and fees.

It also lowers the risk of overlooking an account, missing a required minimum distribution (RMD), or accidentally leaving part of your retirement savings sitting uninvested.

Failing to update beneficiaries

A 401(k) rollover is one of the best times to review your beneficiary designations, yet many retirees overlook it. Retirement accounts are distributed according to the beneficiary form on file, even if your will says something different.

Leaving an ex-spouse, deceased relative, or outdated designation in place could delay distributions, create legal disputes, and send retirement savings to someone you never intended to inherit them.

Bottom line

Small mistakes when rolling over a 401(k) often create unnecessary taxes, penalties, or years of missed investment growth. The safest approach for most retirees is a direct trustee-to-trustee rollover, which avoids mandatory withholding, eliminates the 60-day deadline, and reduces the chance of costly tax errors.

Before moving your retirement savings, it's also worth confirming how your new account will invest the money and whether the rollover changes your future withdrawal options.