Inherited Pension: Lump Sum vs. Monthly Payments Calculator

When you inherit a pension — or when a pension plan offers a buyout — you typically face a binary choice: take a one-time lump sum, or receive guaranteed monthly payments for life. This calculator shows which option generates more lifetime income based on your investment return assumption, tax situation, and how long you expect to live.

When the lump sum is usually better

• You expect to live a long time. Counterintuitively, a long life expectancy often favors the lump sum — because the invested account keeps growing, while a long life makes cumulative payments larger only linearly. But this depends heavily on the investment return.
• The investment return exceeds the pension's implicit payout rate. Divide annual payments by the lump sum: if $21,600 / $300,000 = 7.2%, and you can consistently earn more than 7.2% in a diversified portfolio, the lump sum can theoretically never run dry.
• You want to leave an inheritance. Monthly pension payments typically stop at death (or after a spouse's survivor benefit period). An invested lump sum can pass to heirs.
• The pension sponsor has financial risk. PBGC insurance covers terminated pension plans up to a statutory limit — but if payments exceed that limit, a financially troubled pension poses real default risk. The lump sum eliminates that exposure.
• You can roll the lump sum to an IRA. Many pension lump sums qualify for direct rollover to a traditional IRA — deferring all taxes until you withdraw. Monthly pension payments are taxed immediately each year, creating a meaningful advantage for the IRA rollover path.

When monthly payments are usually better

• You need guaranteed income you can't outlive. A pension guarantees income regardless of market performance. An invested lump sum can be depleted by a bad sequence of returns early in retirement — a real risk if markets drop 30% in year two.
• You're a conservative investor. The lump sum analysis only looks attractive at moderate-to-good investment returns (5–7%+). At 2–3% (CDs, bonds), monthly payments often win decisively.
• You have a shorter life expectancy. If health issues suggest you're unlikely to reach a normal life expectancy, the break-even calculation shifts sharply toward monthly payments (you'd need to live long enough to collect payments that exceed the lump sum's value).
• The pension has a generous survivor benefit. A 100% joint-and-survivor option that covers a spouse for life has significant value not captured in the basic break-even math.

The IRA rollover advantage

If the lump sum comes from a qualified pension or 401(k), you typically can execute a direct rollover to a traditional IRA — transferring the entire amount without triggering immediate income tax. This is almost always superior to taking the lump sum as a cash payout, because:

• A $300,000 cash payout might result in $80,000+ in federal income tax in the distribution year (depending on your bracket), leaving only ~$220,000 to invest.
• A $300,000 IRA rollover keeps the full $300,000 growing tax-deferred.
• You control when and how much you withdraw — allowing bracket-management strategies unavailable with fixed monthly pension payments.

The IRS requires a direct trustee-to-trustee transfer to avoid mandatory 20% withholding. Do not accept a check made out to you if your intention is a rollover.

Inherited annuity vs. inherited pension — different tax rules

If the asset you inherited is a non-qualified annuity (one the decedent funded with after-tax dollars, not inside a 401(k) or IRA), the tax treatment is different from a pension:

• Lump sum (surrender value): Only the gain above the decedent's cost basis is taxable — not the full amount.
• Annuitized payments: Each payment has a tax-free "exclusion ratio" (the portion that is return of basis) and a taxable gain portion.
• 5-year rule: Non-spouse beneficiaries of annuities must fully distribute within 5 years, or elect to annuitize within 1 year of the owner's death.

The calculator above models the pension/qualified plan scenario (fully taxable). For inherited non-qualified annuities, the effective tax burden on monthly payments is lower — which makes the monthly payment option somewhat more attractive than this calculator shows.

Common scenarios

Scenario: $350,000 lump sum or $1,900/month — age 62, single

Annual payments = $22,800. Payout rate = 22,800 / 350,000 = 6.5%. At 6% return, the invested lump sum earns $21,000/yr — slightly less than the $22,800 in payments. The lump sum slowly depletes. Break-even is roughly 32–35 years (age 94–97 depending on taxes). For most 62-year-olds, this is at or past realistic life expectancy — suggesting the lump sum (especially via IRA rollover) is competitive or favorable.

Scenario: $200,000 lump sum or $2,200/month — age 70, married

Annual payments = $26,400. Payout rate = 26,400 / 200,000 = 13.2%. At 6% return, the invested $200K earns $12,000/yr — far below the $26,400 payments. The lump sum depletes in roughly 10–11 years (age 80–81). If both spouses are in good health, monthly payments are the clear winner here.

Scenario: $500,000 lump sum or $2,000/month — age 58, married

Annual payments = $24,000. Payout rate = 24,000 / 500,000 = 4.8%. At 5% return, the lump sum earns $25,000/yr — more than the $24,000 in payments. The invested lump sum never depletes at this return rate. Rolling the $500K to a traditional IRA and managing withdrawals strategically almost certainly beats the monthly pension payments in lifetime value.