Pension lump sum vs annuity: free money forever vs. a big pile now

By Tom, CPA · Updated October 25, 2026

TL;DR: To compare a pension lump sum with a monthly annuity, compute the implied return (discount rate) that makes the lump sum equal the payments over your expected lifetime, then weigh longevity, survivor needs, inflation, PBGC protection, and taxes. A lump sum can generally be rolled to an IRA tax-free; annuity payments are taxed as received.

Educational only, not tax, legal, or investment advice. Examples are illustrations, not predictions. Rules and limits change; verify current figures and talk to a qualified professional about your situation.

The envelope from the pension plan says: "Choose one. A) $2,000 a month for the rest of your life. B) $330,000 today." One option looks like a slow drip of free money; the other looks like a lottery win. The vibes say take the pile. The math is less obvious than the vibes.

This decision often lands right when people retire early or leave a job, and it's usually permanent. Let's walk through how to compare the two with numbers, not gut feelings, and which non-math factors decide the close calls.

CPA Warning Label: A lump sum is an irreversible swap of a lifetime guarantee for a pile of money that you now have to invest, make last, and protect from yourself.

Implied return math

The key number is the implied return: the interest rate at which the lump sum could buy the same stream of payments over your expected lifetime. If you could reliably earn more than that rate, the lump sum looks attractive; if not, the annuity is a better deal.

Illustration (assumptions): Fran, 60, is offered $2,000 a month for life (no inflation adjustment) or $330,000. Assume she lives to 87 (27 years, 324 payments).

• At a 5% annual discount rate (compounded monthly), 324 monthly payments of $2,000 are worth about $355,000 today, more than the lump sum.
• At about 5.7%, they're worth $330,000.

So the implied return is roughly 5.7% if she lives to 87. If she lives to 95, it rises to about 6.5%; if she dies at 75, it drops to about 1.2%. To match the annuity with the lump sum, she'd need to earn about 5.7% a year, net of fees, with withdrawals of $24,000 a year, without running out. That's possible with a balanced portfolio, but not guaranteed, and the annuity carries no market risk.

Plans calculate lump sums using IRS-prescribed interest rates and mortality tables (Section 417(e) segment rates). When interest rates rise, lump sums shrink, and vice versa. If your plan lets you choose timing, the lump-sum value can change noticeably from one year to the next.

Longevity and survivor options

• Longevity: an annuity is insurance against living a long time. If your parents lived into their 90s and you're healthy, the annuity's value rises.
• Health: serious health issues favor the lump sum, especially if no survivor needs income.
• Survivor annuities: married participants generally receive a qualified joint and survivor annuity unless the spouse consents in writing to another form. A 50% or 100% survivor option lowers the monthly amount but protects the spouse.
• Inflation: most private pensions aren't adjusted for inflation. At 3% inflation, $2,000 in 2026 buys about $1,100 of today's goods after 20 years. Early retirees face more years of that erosion.

PBGC protection

Private-sector defined benefit plans are generally insured by the Pension Benefit Guaranty Corporation (PBGC). If a plan fails, PBGC pays benefits up to a legal maximum, which depends on your age when benefits start and the form of payment, and is lower for younger retirees. Most participants' benefits are fully covered, but very large pensions, and benefits taken at young ages, may exceed the guarantee. Check PBGC's maximum guarantee table for your age and year. Government plans (state and local) aren't PBGC-insured; they're backed by the government sponsor.

A weak plan sponsor or an underfunded plan is a reason to lean toward the lump sum, while a strong sponsor with a well-funded plan supports the annuity. Your plan's annual funding notice shows its funded percentage.

Tax and rollover

• Lump sum: generally an eligible rollover distribution. A direct rollover to an IRA or another plan avoids current tax. If paid to you, the plan must withhold 20% for federal tax, and you have 60 days to roll over the full amount, including the withheld part, to avoid tax.
• Annuity: payments are taxed as ordinary income when received (minus any after-tax basis), and can't be rolled over.
• 10% additional tax: if you take a lump sum in cash before 59½, it may apply unless an exception fits, such as separation from service in or after the year you turn 55. Annuity payments that are part of a series of substantially equal periodic payments for life generally aren't subject to it.
• Roth conversions: a lump sum rolled to an IRA can feed a conversion ladder; an annuity's income uses up bracket space instead.

Decision factors

A step-by-step comparison worksheet

1. Get both numbers in writing: the lump sum and every annuity form offered (single life, 50%, 75% and 100% joint and survivor, period certain).
2. Pick three ages at death: a pessimistic one, your expected one, and an optimistic one (say 75, 87 and 95).
3. Compute the implied return for each with a spreadsheet's RATE function: number of monthly payments, the monthly payment, and the lump sum as present value.
4. Compare with safe yields. If high-quality bonds or Treasuries of a similar length yield more than the implied return, the lump sum is relatively generous. If they yield less, the annuity is.
5. Adjust for inflation. A fixed annuity loses purchasing power; a lump sum invested in inflation-protected bonds or stocks might not.
6. Layer in the qualitative factors from the table above and decide.

This worksheet won't produce certainty, because nobody knows their own date of death (thankfully). It turns a gut call into a comparison of a known guarantee with a range of plausible outcomes. In Fran's case, the 1.2% to 6.5% spread tells the story: the lump sum wins if she dies early, the annuity wins if she lives long, and her health and family history are the tiebreakers.

One more wrinkle for early retirees: many plans offer a smaller annuity if you start before the plan's normal retirement age, and some offer a temporary "bridge" supplement until Social Security begins. Run the worksheet for each start age the plan allows, because waiting a few years can raise the monthly amount meaningfully while the lump sum changes less.

A middle path

Some plans allow a partial lump sum and a partial annuity. If not, you can take the lump sum, roll it to an IRA, and later use part of it to buy an annuity. Commercial annuities are often more expensive than the plan's built-in one, so compare quotes before assuming you can recreate the pension on the open market. For early retirees, combining a lump sum (for flexibility and conversions) with Social Security as the inflation-adjusted lifetime income floor is a common approach, as is the reverse: take the annuity as a floor and keep investment accounts for flexibility. See bridge accounts for sequencing.