How to Calculate a Lump Sum Payment: Pensions, Settlements, and Taxes

To calculate a lump sum payment, you convert the future payments you’re owed into a single amount payable today by applying a discount rate that accounts for the time value of money. The formula changes slightly depending on whether you’re valuing one future payment or a recurring stream, and the discount rate changes dramatically depending on the source: pension plans use IRS-published segment rates near 5%, while structured settlement buyers commonly apply rates of 9% to 18%. The underlying principle is the same across every situation: a dollar you’d receive years from now is worth less than a dollar in your hand today, and the lump sum is simply the present-day equivalent of that future money.

What You Need Before You Run the Numbers

Four inputs drive every lump sum calculation. Pull them from your pension statement, settlement agreement, benefit notice, or buyout offer before you start:

The total future payment amount, meaning the full dollar figure you’d collect if you kept receiving payments through the end of the term or your projected lifetime.
The size of each payment and how often it arrives (monthly, quarterly, or annually).
The number of remaining payment periods. For example, 120 monthly payments covers 10 years; 240 covers 20 years.
The discount rate. Pension plans must use IRS segment rates. Workers’ compensation uses state-published commutation rates. Structured settlement buyers set their own rate based on market conditions and profit margin.

With those four numbers in hand, you can either run the math yourself or sanity-check an offer someone has already made you.

Present Value of a Single Future Payment

The simplest case is one future payment. The formula is:

PV = FV ÷ (1 + r)ⁿ

PV is present value, the lump sum today.
FV is future value, the payment you’d otherwise receive later.
r is the discount rate per period, written as a decimal.
n is the number of periods until the payment arrives.

Say you’re owed a single $100,000 payment 10 years from now, and the applicable discount rate is 5%. Add 1 to the rate: 1 + 0.05 = 1.05. Raise it to the 10th power: 1.05¹⁰ = 1.6289. Divide: $100,000 ÷ 1.6289 = $61,391. That $61,391 is the present value. Invested at 5% annually, it would grow to $100,000 in 10 years.

Present Value of a Series of Payments

Most real lump sum questions involve a stream of equal payments, not a single future amount. For that, use the present value of an annuity formula:

PV = PMT × [(1 − (1 ÷ (1 + r)ⁿ)) ÷ r]

PMT is the dollar amount of each individual payment.
r is the discount rate per period, as a decimal.
n is the total number of payment periods.

Suppose you’re entitled to $1,000 a month for 10 years, which is 120 payments, and the annual discount rate is 6%. Because the payments are monthly, convert the rate to a per-period figure: 0.06 ÷ 12 = 0.005. Plug the numbers in: PV = $1,000 × [(1 − (1 ÷ 1.005¹²⁰)) ÷ 0.005]. Working through, 1.005¹²⁰ = 1.8194, so PV = $1,000 × [(1 − 0.5496) ÷ 0.005] = $1,000 × 90.07 = $90,074. In other words, you’d take roughly $90,074 today in exchange for giving up $120,000 spread over the next decade.

Present value measures only the current worth of the incoming cash. Legal fees, surrender charges, and other costs of obtaining the lump sum come off the top. Subtract them to get the net present value, which is the real financial benefit of accepting the deal.

How Pension Lump Sums Are Calculated

Pension lump sums follow the same present-value math but use federally mandated inputs instead of negotiated ones. The plan actuary first projects how many monthly checks you’d likely collect over your lifetime, using a government-approved unisex mortality table. For distributions starting in 2026, plans use the table published in IRS Notice 2025-40.¹ That table assigns a probability to each future month that you’ll be alive to collect, and those probabilities feed the projected total lifetime benefit.

The discount rate comes from the IRS’s three segment rates, which track corporate bond yields and are updated monthly. The first segment covers payments expected within five years, the second covers years five through twenty, and the third covers payments beyond twenty years.² For January 2026, the adjusted 24-month average segment rates are 4.75%, 5.25%, and 5.74%.³ Higher rates shrink the lump sum because future dollars are discounted harder; lower rates enlarge it.

You can approximate your own number by running the annuity formula with your monthly benefit, the segment rate matching each time band, and a reasonable life-expectancy figure. But the plan’s precise calculation depends on its specific mortality assumptions, so treat your version as a ballpark check against the offer on your benefit statement, not a binding figure.

Workers’ Compensation Commutation

Workers’ comp lump sums are produced through commutation, which converts your remaining weekly or biweekly indemnity benefits into a single payment. State agencies publish commutation tables containing multipliers tied to the number of benefit weeks you have left. Your remaining benefit total is multiplied by the applicable factor, which already builds in the discount rate and payout timeline.

A permanent disability rating can push the total higher if your injury caused a lasting loss of earning capacity. Future medical expenses are sometimes folded in as well, often adjusted upward for expected healthcare inflation before being discounted back to today.

Discount rates and commutation methods vary by state, and some are set by statute. The same injury with the same remaining benefits can produce meaningfully different lump sums depending on jurisdiction, so verify the math against your state’s workers’ compensation board tables or with an attorney who handles commutations in that state.

Structured Settlement and Annuity Buyouts

When a factoring company offers to buy out your structured settlement or annuity payments, it uses the same present value formula, but with a discount rate that reflects its cost of capital plus profit. Industry rates typically run 9% to 18%, and can climb higher for payments scheduled far in the future. Compare that to pension segment rates near 5%, and the gap explains why buyout offers return a fraction of the remaining face value.

Picture $200,000 in structured settlement payments remaining over 15 years. Run those payments through a 12% discount rate and the present value drops to roughly $72,000, which is about 36 cents on the dollar. At 16%, the number is lower still. The payment schedule matters as much as the rate: payments due in the next year or two lose little value, while payments due 15 or 20 years out are discounted so aggressively they contribute almost nothing. Because buyers apply different rates, collect several offers before committing. A single percentage point of rate difference can shift a large settlement by thousands.

Federal law requires court approval before any structured settlement payment rights can be sold, and buyers that skip court approval owe a 40% excise tax on the discount.⁴ Build that approval timeline into any offer comparison.

Taxes Change What the Lump Sum Is Actually Worth

Gross present value isn’t what you keep. How a lump sum is taxed depends entirely on what produced it:

Damages for personal physical injuries or physical sickness are excluded from gross income, including lost wages caused by the physical injury. Punitive damages are not covered.⁵
Settlements for emotional distress, defamation, discrimination, or humiliation are generally taxable unless the emotional distress arose from a physical injury. A narrow exception covers reimbursement of unreimbursed medical expenses related to the emotional distress.⁶
Employment settlement amounts for lost wages, lost benefits, or lost business income are taxable as ordinary income unless a personal physical injury caused the loss. Awards from age, race, gender, religion, or disability discrimination suits are not excludable.⁶
Workers’ compensation benefits are generally excluded from gross income.⁵
Pension lump sum distributions are ordinary income in the year received, and the plan must withhold 20% for federal income tax unless you direct a rollover to an IRA or another qualified plan. Pulling pension money before age 59½ also triggers a 10% additional tax unless an exception applies.⁷⁸⁹

Punitive damages are almost always taxable, regardless of the underlying claim. The lone exception is wrongful death cases in states where only punitive damages are available under state law.⁶ Because taxes can swing after-tax value by tens of thousands of dollars, work out the tax hit before you compare lump sum offers against the stream you’d be giving up.

1
Internal Revenue Service. Updated Static Mortality Tables for Defined Benefit Pension Plans
2
Office of the Law Revision Counsel. 26 U.S. Code 417 – Definitions and Special Rules for Purposes of Minimum Survivor Annuity Requirements
3
Internal Revenue Service. Pension Plan Funding Segment Rates
4
Office of the Law Revision Counsel. 26 U.S. Code 5891 – Structured Settlement Factoring Transactions
5
Office of the Law Revision Counsel. 26 U.S. Code 104 – Compensation for Injuries or Sickness
6
Internal Revenue Service. Tax Implications of Settlements and Judgments
7
Office of the Law Revision Counsel. 26 U.S. Code 3405 – Special Rules for Pensions, Annuities, and Certain Other Deferred Income
8
Internal Revenue Service. Topic No. 412, Lump-Sum Distributions
9
Office of the Law Revision Counsel. 26 U.S. Code 72 – Annuities; Certain Proceeds of Endowment and Life Insurance Contracts