Pension Lump Sum vs. Monthly Annuity Calculator

Most pension plans give you one shot at this choice: take a guaranteed monthly payment for life, or accept a single lump sum you invest yourself. The decision is irrevocable. This calculator runs the break-even math at multiple investment return assumptions and shows year by year when — if ever — the pension catches up to the lump sum, so you can see which path favors you given your specific numbers and life expectancy.

How to read the results

The calculator asks: if you take the lump sum and invest it — while withdrawing the same income the pension would have paid — how many years does the lump sum last? That year is the break-even point.

• If you live past the break-even age: the pension would have paid you more in total lifetime income than you got from the lump sum (which has now run out).
• If you die before the break-even age: the lump sum still has a balance — an asset you could leave to heirs. The pension paid you less in total, but you didn't need the income for as long.
• The return rate matters enormously. At 0% return, the break-even is just lump sum ÷ annual pension — typically 12–15 years. At 5% return, the lump sum lasts 20–25+ years because investment earnings extend the run. Higher assumed returns favor the lump sum; lower returns favor the pension.

What the break-even math misses

The break-even is a necessary starting point, but three factors regularly change the conclusion:

Spouse and survivor risk

A life-only pension dies with you. If your spouse depends on that income, the lump sum becomes more attractive — or you need to elect a joint-and-survivor (J&S) option that reduces your monthly benefit by 5–20% depending on your ages and the benefit percentage elected. The survivor benefit protects your spouse at the cost of a lower break-even math for you. Run the numbers with the reduced J&S monthly to see how it shifts the break-even.

Investment skill and sequence-of-returns risk

The assumed return rate only matters if you actually earn it. A retiree who earns 5% average returns but withdraws through a bad first-decade sequence can exhaust the lump sum far earlier than the break-even suggests. The pension eliminates this risk entirely — you get the check regardless of what markets do. If you have limited investment experience or low tolerance for drawdowns, the pension's guarantee is worth more than the break-even implies.

PBGC insurance and employer credit risk

If you take the pension, your payments are guaranteed by the Pension Benefit Guaranty Corporation (PBGC) up to a maximum annual benefit (see PBGC maximum guarantee limits). Most retirees are within the PBGC cap, meaning employer insolvency doesn't eliminate their pension. If your pension would exceed the PBGC cap, or if your employer has shaky credit, the lump sum removes that default risk.

COLA pensions vs. flat pensions

A COLA (cost-of-living adjustment) changes the math significantly. A pension that grows 2–3% per year is worth considerably more than a flat one — but many corporate pensions have no COLA at all. Government pensions (FERS, CalPERS, CalSTRS, many state systems) typically have full or partial COLA provisions.

In the calculator, set COLA to match what your plan document says. If your pension is flat, set 0%. A flat $2,500/month in 20 years buys roughly 55% of what it buys today at 3% inflation — an invisible benefit erosion that the pension annuity path must be evaluated against.¹

Tax treatment of each option

The lump sum and monthly pension are generally taxed similarly in the long run — both as ordinary income as you receive or withdraw funds from pre-tax accounts — but the timing and mechanics differ:

• Monthly pension: Fully taxable as ordinary income in the year received (if paid from a pre-tax pension plan). Withholding is automatic. Predictable for IRMAA planning and bracket management.
• Lump sum rolled to IRA: No immediate tax. You control the timing and amount of withdrawals, which creates opportunities — Roth conversions during low-income years, harvesting 0% long-term capital gains on non-qualified assets, sizing income to stay under IRMAA thresholds. The flexibility is real.
• Lump sum taken as cash (not rolled to IRA): Taxed as ordinary income in full that year, potentially at 24–37%. If you're within 5 years of pension start, also subject to 20% mandatory withholding. This is almost always worse — roll to an IRA instead.

The survivor benefit decision tree

If you're married, the lump-sum vs. annuity decision intersects with the survivor benefit election. Most plans offer:

*Reduction percentages are actuarially determined by your plan based on both spouses' ages. Your plan documents show the exact amounts.

When evaluating the J&S option vs. the lump sum, enter the reduced J&S monthly amount into the calculator. The survivor protection is essentially an insurance premium — the reduction buys an annuity that continues to your spouse. Whether that insurance is worth the cost depends on your spouse's age, health, and other income sources.

1. U.S. Bureau of Labor Statistics — Consumer Price Index. Historical CPI data used to illustrate purchasing-power erosion for flat vs. COLA pensions. COLA analysis verified against 2026 CPI-W series.
2. Pension Benefit Guaranty Corporation — Maximum Guarantee. PBGC guarantees pension benefits up to an annual maximum that adjusts each year. Retirees should verify current limits at PBGC.gov when making the lump-sum decision.
3. IRS Publication 575 — Pension and Annuity Income. Tax treatment of pension distributions, lump-sum distributions, and IRA rollovers. Covers the 20% mandatory withholding rule on indirect rollovers and the 60-day rollover window.
4. Society of Actuaries — Post-Retirement Experience Report. Actuarial longevity data underlying life expectancy assumptions used as reference benchmarks. The SOA RP-2014 and MP-2021 tables inform pension plan break-even analysis.

Break-even formulas use standard annuity present-value mathematics. No regulatory values are hardcoded — all outputs depend on your inputs. Tax and survivor benefit commentary reflects 2026 rules.