Rolling a Pension Lump Sum Into an IRA: Tax Mechanics

Rolling a pension lump sum into an IRA triggers specific tax rules: a 60-day window to complete the rollover, mandatory 20% withholding on direct distributions unless you elect a trustee-to-trustee transfer, and a pro-rata calculation that can trap pre-tax and after-tax contributions. Understanding these mechanics prevents costly mistakes, missed deadlines, and tax surprises.

The two paths: direct and indirect rollover

When your pension plan distributes a lump sum, you have two routes to get the money into an IRA.

Direct rollover (trustee-to-trustee transfer)

The pension trustee writes a check payable to the IRA custodian on your behalf. The money never passes through your hands. There is no withholding, no 60-day clock, and no tax event. This is the cleanest path and is almost always the best choice.

Example: Your pension plan distributes $500,000. You elect a direct rollover. The plan trustee sends a check to Fidelity (or your IRA custodian) made out to “Fidelity, FBO [your name]” (FBO = “for the benefit of”). The $500,000 lands in your IRA untouched.

Indirect rollover (you receive the check)

The pension plan mails you a check for the full $500,000. You must deposit it into an IRA within 60 calendar days. If you miss the 60-day window, the distribution becomes taxable income, and if you’re under 59.5, you’ll owe a 10% early withdrawal penalty on top.

Because you received the check, the plan administrator is required to withhold 20% for federal income tax, even if you intend to roll the full amount over. So you receive $400,000 (80% of $500,000) and must come up with the $100,000 withholding out of pocket to complete the full rollover. If you only deposit the $400,000, the $100,000 withholding is treated as a taxable distribution (and the 10% penalty applies if you’re under 59.5).

The 60-day window and common pitfalls

The 60-day period begins when you receive the distribution, not when it’s processed by the plan. If the check arrives on March 15, your deadline is May 14 (60 calendar days later; weekends and holidays count).

Common mistakes:

• Depositing on day 61 (missing the deadline by one day). The IRS has no exceptions for late deposits; the entire distribution becomes taxable.
• Delaying the deposit, forgetting the deadline, and discovering the mistake months later when filing taxes.
• Thinking the 60 days starts from the check date (it doesn’t; it’s the receipt date).

If you miss the deadline, you can request a waiver from the IRS (Form 8329), but waivers are granted only in narrow circumstances (fire, flood, death, serious illness, or actions of the custodian beyond your control). A simple oversight does not qualify.

Withholding: what happens and how to cope

When the pension plan mails you a check for an indirect rollover, it must withhold 20% for federal income tax. This is mandatory—the plan cannot waive it, and you cannot opt out.

If your distribution is $500,000:

• You receive: $400,000
• Withheld: $100,000
• Your deadline: 60 days to deposit the $400,000 into an IRA

Here’s the trap: if you only have the $400,000 and deposit it into the IRA, you are short $100,000. To complete a full rollover, you must use your own funds to make up the difference. If you don’t, the $100,000 shortfall is treated as a taxable distribution.

Example of a shortfall: You receive the $400,000 and deposit it into your IRA within 60 days. You report the $100,000 withholding as a tax payment when you file your return. But the IRS views the $500,000 pension distribution as follows:

• $400,000 rolled to IRA (no tax)
• $100,000 not rolled (taxable ordinary income)
• 10% penalty ($10,000) if you’re under 59.5

You’ll owe tax on $100,000 plus a penalty, even though that $100,000 was withheld. The withholding is merely a prepayment toward your final tax bill.

The pro-rata rule: a tax trap for two-IRA situations

If you already have one or more IRAs with pre-tax balances (from prior rollovers, SEP-IRA contributions, or traditional IRA contributions), the pro-rata rule applies to any rollover.

The rule: the IRS treats all your traditional IRAs as a single pool for tax purposes. If you convert a portion of your IRA to a Roth or take a distribution, the tax is calculated on the entire pool, not just the account you’re touching.

Scenario where it matters:

• You have a traditional IRA with $50,000 of pre-tax contributions and no earnings.
• You roll a $100,000 pension distribution into a second IRA (which is now all pre-tax).
• You want to convert $100,000 to a Roth IRA.

You might assume: “I’ll convert the pension rollover IRA (100% pre-tax), pay tax on $100,000, and the $50,000 old IRA stays untouched.”

But the pro-rata rule says: Your total pre-tax IRA balance is $150,000. You’re converting $100,000. The tax is calculated as: $100,000 / $150,000 = 66.67% pre-tax. So you owe tax on 66.67% × $100,000 = $66,667 on the conversion.

To avoid the pro-rata trap, some people roll the pension distribution into a separate IRA and then immediately perform a Roth conversion, but they must be careful about the timing and the composition of their other IRAs.

After-tax contributions complicate the picture

Some pension plans allow you to have made after-tax contributions (not Roth, but post-tax dollars). When you roll a lump sum, these after-tax dollars can be split:

• After-tax contributions can be rolled to a Roth IRA (and grow tax-free).
• Pre-tax contributions and earnings must go to a traditional IRA (unless you convert them to Roth, which triggers tax).

This separation requires coordination with your pension plan and IRA custodian. Some plans allow a “split rollover” where they issue two checks: one for pre-tax and one for after-tax. Others don’t, requiring you to deposit everything and then move the after-tax portion via a taxable conversion.

If done carefully, rolling after-tax contributions to Roth is tax-efficient. If done carelessly, you can inadvertently owe tax on contributions you’ve already taxed.

State income tax considerations

Some states tax pension income; others exempt it. If you’re moving to a low-tax or no-tax state after retirement, rolling a pension to an IRA doesn’t change the state tax treatment of the pension itself (it was already yours). But the future earnings on the IRA may escape state tax if you move. Conversely, rolling to an IRA and then converting to Roth doesn’t reduce state tax on the conversion in states that still tax Roth conversions as income.

Check your state’s treatment of pension rollovers and Roth conversions before executing the rollover.

Steps to execute a clean rollover

1. Contact your pension plan administrator and request a direct rollover form.
2. Specify the IRA custodian: Provide the name, address, and plan number of the IRA where the money will land.
3. Ask the plan to issue a check payable to the custodian FBO you (not to you directly).
4. Confirm the destination IRA is funded and ready to receive the deposit.
5. Verify receipt within 5–10 business days; the custodian will send a confirmation.

If you receive an indirect rollover (check to you), deposit it into your IRA immediately—do not wait until day 59. Processing delays or postal delays can cause you to miss the 60-day window.

Mistakes and remedies

Missed the 60-day deadline? Contact the IRS on Form 8329 (Application for Extension of Time To Perform Certain Acts) and explain why (serious illness, death in the family, custodian error). Waivers are rare but possible.

Only rolled part of the distribution? The remainder is taxable. File Form 1040 and Schedule 1, report the taxable portion as “Other Income,” and pay tax plus the 10% penalty if applicable.

Rolled to the wrong account? If it went to a non-IRA account (e.g., a brokerage account by mistake), you have no rollover protection and the full amount is taxable.

Withholding exceeded your tax liability? The excess becomes a tax refund. File your return; you’ll receive it.

See also