A defined-benefit pension often gives you a fork in the road: take a single, large lump sum on the day you retire, or let the plan pay you a smaller but guaranteed monthly annuity for the rest of your life. This lump sum calculator shows the two sides side by side — how long it takes the monthly checks to "earn back" the cash offer, how much money the annuity pays out in total, and whether the lump sum, if invested at a reasonable return, would actually outlast the guaranteed pension.
Enter your offer in the boxes and the breakeven point updates instantly. There is no single correct answer; the right choice depends on your health, your other savings, your risk tolerance, and whether you want to leave money to heirs. But the numbers below are the starting point for that decision.
How to Use
- Enter the Lump Sum Offer — the gross one-time payout your plan quotes before tax. A typical offer might be $500,000 for someone with a long service history.
- Type the Monthly Annuity Payment — the monthly pension check you would receive instead. On the same profile this is often around $3,000 per month.
- Set the Annuity Payout Period. If your annuity is for life, use a realistic life-expectancy estimate — 20 to 30 years is common for a healthy 60-something. If it is a fixed period certain, enter that exact number of years.
- Choose an Expected Investment Return. This is only used to project what the lump sum might earn if you invested it yourself. A conservative 3%–5% per year is more defensible than 8%–10% when you are relying on the money for retirement income.
- Read the result card:
- Total Annuity Paid — every monthly check added up over the payout period.
- Breakeven — the month (and year) at which the cumulative annuity payments equal the lump sum. Live past this point and the annuity has paid out more cash than taking the lump.
- Annuity Extra Over Lump Sum — the difference between total annuity paid and the cash offer.
- Invested Lump Balance After Period — what the invested lump would be worth at the end of the payout period if you withdrew the same $ amount each month. A negative number means the self-invested lump runs out before the annuity period ends.
The Breakeven Idea
The simplest comparison ignores investment growth and asks: how many monthly checks add up to the cash offer?
Breakeven months = Lump Sum ÷ Monthly Annuity
On the default figures — a $500,000 lump sum and a $3,000 monthly annuity — the breakeven point is 500,000 ÷ 3,000 = 166.7 months, or about 13.9 years. In plain English, if you live roughly 14 years after retirement, the annuity has handed you back the equivalent of the lump sum; every check after that is pure "victory" for the annuity, while every month you do not reach that point is a month the lump-sum option would have left you ahead.
Over the full 25-year payout period, the annuity pays 3,000 × 300 = $900,000 — $400,000 more than the $500,000 cash offer, before counting any growth on that money.
The Investment-Growth Twist
The breakeven above is a useful floor, but it is not the whole story, because the lump sum can be invested and the annuity cannot be outlived. The calculator models the lump sum as a balance that grows at your assumed annual return and then sheds the same $3,000 withdrawal each month.
At a 4% annual return, that $500,000 balance, drained by $3,000 every month, lasts only about 244 months (roughly 20 years) before hitting zero. Extend the annuity to 25 years and the invested lump ends the period roughly $185,500 short. That is the power of a lifetime guarantee: the annuity keeps paying even after a self-managed portfolio would be exhausted.
Push the expected return up to 5% on a $1,200,000 lump sum with a $5,000 monthly check and the math flips the other way — the annual interest alone is about $60,000, exactly covering the $5,000 monthly withdrawal, so the principal is never touched. Higher lump sums and conservative withdrawals are where the lump-sum choice shines.
Examples
Example 1 — The default offer. A retiring teacher is offered $500,000 cash or $3,000 per month for life. Using a 25-year horizon and a 4% return, the annuity pays $900,000 in total, breakeven lands at 166.7 months (13.9 years), and the invested lump ends the 25-year period about $185,500 in the red. For someone in average health with no strong heir motive, the guaranteed check is hard to beat.
Example 2 — A million-dollar package. A senior executive is offered $1,200,000 cash or $5,000 per month for 30 years. At a 5% return, total annuity paid is $1,800,000, breakeven is 240 months (20 years), and the invested lump still ends the period at $1,200,000 because the withdrawal equals the interest. Here the lump sum preserves principal while also leaving a large estate — a very different trade-off from Example 1.
Example 3 — The zero-return caution. If you assume the lump sum simply sits in cash at 0%, the $500,000 drained by $3,000 a month is gone after 167 months, and the ending balance over 25 years is -$400,000. This shows how much the "expected return" assumption drives the conclusion — be conservative.
FAQ
Should I take a pension as a lump sum or an annuity?
Take the annuity if you expect a long retirement, have little other guaranteed income, or worry about managing investments in retirement. Take the lump sum if you have substantial other savings, good financial discipline, a shorter life expectancy, or want flexibility to spend or leave an inheritance. Use the breakeven year from this calculator — living past it favors the annuity.
What is the breakeven age for a pension lump sum?
The breakeven point is the date when cumulative monthly annuity payments equal the lump sum. Divide the lump sum by the monthly annuity to get the number of months, then divide by 12 for years. On a $500,000 lump sum and $3,000 monthly check, breakeven is about 167 months, or 14 years after you start the pension.
Is the monthly annuity payment guaranteed for life?
Most defined-benefit annuities pay for your lifetime (and often a reduced 50%–100% benefit for a surviving spouse), backed by the plan and, in the U.S., partly insured by the Pension Benefit Guaranty Corporation. A lump sum carries no such guarantee — once it is invested and spent, it is gone.
What rate of return should I assume on the lump sum?
For retirement income planning, a conservative 3%–5% annual return is the most honest assumption. Promising yourself 8%–10% over a 30-year drawdown sequence understates the risk of the lump-sum choice. Stress-test your decision at 0% and 3% as well as your target figure.
Can I roll the lump sum into an IRA?
In most cases a direct rollover of a qualified lump sum into a traditional IRA lets you defer taxes and continue investing. If you instead take a cash distribution, the plan withholds 20% for taxes and you may owe more at filing, plus a 10% penalty if you are under 59½. Confirm the rollover rules with your plan administrator and a tax professional.
What happens to the lump sum if I die early?
With the lump sum, whatever remains belongs to your estate and can pass to heirs. With a pure life annuity, payments stop when you die (though a joint-and-survivor or period-certain option can continue payments to a spouse or for a set number of years). If leaving money to family is a priority, the lump sum is the more flexible vehicle.
Disclaimer
This lump sum calculator is provided for informational purposes only and does not constitute financial, tax, investment, or legal advice. Breakeven and projected balances are estimates based on the inputs you enter and a simple growth-and-withdrawal model; they ignore taxes, inflation, survivor options, fees, and mortality assumptions specific to your pension plan. Actual lump-sum offers and annuity rates vary by plan, age, health, and marital status. Always review your individual pension election with a qualified retirement planner and tax advisor before making an irreversible decision.