Lump Sum or Annuity — Why This Decision Is So Hard

A pension lump sum and a lifetime annuity aren't really two prices for the same thing — they're two completely different bets. The lump sum hands you a fixed amount today that you invest and manage yourself. The annuity hands a third party your money in exchange for a guaranteed paycheck for as long as you live, no matter how long that turns out to be. Comparing them fairly means putting both in the same currency: present value, what all those future monthly checks are worth in today's dollars.

How the Present Value Comparison Works

Each future payment gets discounted by your assumed investment return — money next year is worth less than money today, because you could have invested today's money and grown it. Add up every discounted year's payment, and you get the pension's true value in today's terms, directly comparable to the lump sum on the table.

What "Break-Even Return" Actually Tells You

This is the single most useful number this calculator produces: the annual return your invested lump sum would need to earn, every year, for the rest of your life, just to match what the guaranteed pension pays. If that number is low (say, 3-4%), the lump sum looks attractive — you don't need to take much investment risk to beat the pension. If it's high (8%+), the pension is doing you a real favor that's hard to replicate safely.

Factors That Should Tip Your Decision

What This Model Doesn't Capture

• Taxes — both are generally taxed as ordinary income, but a lump sum rolled into an IRA defers tax differently than monthly pension income
• Survivor benefits — many annuities offer a reduced payment that continues to a spouse; this model assumes payments stop at your life expectancy
• Longevity risk — if you live well past your planning horizon, the guaranteed annuity keeps paying long after a self-managed lump sum might run dry
• Pension insurer/plan risk — lump sums eliminate any risk tied to your pension plan's own funding health

Worked Example

Suppose you're offered a $300,000 lump sum, or $1,800/month for life starting at age 62, with no COLA, and you plan to age 90 (28 years). Discounting those payments at a 6% assumed return produces a present value of roughly $290,000 — meaning the lump sum narrowly wins in this scenario, but it's close enough that a slightly more conservative return assumption could flip the answer. That sensitivity is exactly why it's worth running your own numbers rather than going with a rule of thumb.

Where to Go From Here

If you're leaning toward the lump sum, model how it could grow with our compound interest calculator or 401(k) calculator if rolling it into a retirement account. Either way, check how it fits your full retirement picture with the retirement calculator.

Frequently Asked Questions