Calculator
Present Value (Lump Sum Today)
$114,699.21
Valuation Analysis
11.5× each payment: at 6% over 20 years, every $10,000.00 payment in the stream is worth that multiple in present-value terms. The stream's $200,000 in future cash is worth only $114,699.21 today — a $85,300.79 time-value discount (74% of the present value). That gap is the price of waiting, and it is exactly what a lump-sum offer should be judged against.
*The present value result depends entirely on the discount rate chosen; small changes in the rate can change the valuation materially. The tool assumes constant payments and a constant rate with no tax. Educational only, not investment or tax advice.
An annuity is simply a series of equal payments spread over time — a defined benefit super pension, an account-based pension drawdown, a lifetime annuity from an insurer like Challenger, or rental income. The present value of that annuity answers the question every stream of future money raises: what is all those future payments worth in today's dollars, right now? Money received later is worth less than money received today, because today's money can start earning immediately, so each distant payment must be shrunk by the time it is delayed. Add up all those discounted payments and the total is the lump sum that would be economically equivalent to the stream. For Australian retirees this is the math behind the most common either/or decision at retirement: take a lump sum and run an account-based pension, keep a defined benefit pension (CSS, PSS, UniSuper DB, some state schemes), or hand capital to a lifetime annuity for a guaranteed income. The nominal totals make the answer look obvious — twenty years of $18,000 payments 'adds up' to $360,000 — but the present value at a realistic discount rate is usually far less, often half or less of the face total. That gap is the time value of money. This tool computes the present value, shows the gap between face value and today's worth, and gives you the annuity factor so you can judge whether a commutation offer or annuity quote on the table beats keeping the stream.
The classic formula discounts every payment at the periodic rate: present value equals the payment times one minus one plus r raised to the negative n, all divided by r, where r is the per-period rate and n the number of periods. Each payment is worth payment divided by one plus r to the power of its period number, so the first payment is barely discounted and the last payment is discounted for the full journey. The closed form is just the sum of that geometric series. If the rate is zero, the present value is simply the payment times the count — no discounting, face value equals today's worth. The annuity factor — present value divided by one payment — is the workhorse number: it tells you how many payments' worth the stream equals in cash today. A 20-year annual stream at 6% has a factor around 11.5, meaning the whole income stream is worth about 11.5 annual payments as a lump sum. The time-value discount is the face total minus the present value, and the effective annual yield converts a monthly rate into the annual figure for comparison with other investments. When evaluating a real offer, set the discount rate to what you could reasonably earn on a lump sum today — a conservative balanced-portfolio return for super money — because that opportunity cost is what you give up by taking installments instead of cash.
Present value moves sharply with the rate: at 4%, a 25-year $18,000 stream is worth around $281,000; at 7%, only about $207,000. Both numbers are 'correct' — they just reflect different assumptions about what else your retirement money could earn. Before valuing any real offer, settle on a defensible rate tied to your actual asset allocation in retirement — say 5% for a conservative super drawdown plan — and run the valuation at one point higher and one point lower to see how much the answer depends on the assumption.
A lump sum gives control: you can invest it in an account-based pension, spend it, or leave it — but you can also blow it, and Centrelink's means testing treats assets and income differently depending on the choice. A guaranteed DB pension or lifetime annuity enforces discipline you may not have and often enjoys favourable treatment under the income test. This tool prices the economics; the right answer also depends on behaviour and how each option scores against the Age Pension tests. Price both, then let self-knowledge break the tie.
If you are choosing between a defined benefit pension and a lump sum, get a quote for what monthly lifetime income the lump sum would purchase at current annuity rates — Challenger publishes these — and compare it with the pension's payment. The stream with the higher income per dollar of present value is the better deal mechanically. This calculator's annuity factor lets you reverse the same logic: if a commutation offer is far below the computed present value at a fair rate, the trustee's formula is keeping the spread.
When someone offers you future payments for a lump sum (or vice versa), discount the stream at the return you could realistically earn by investing that lump sum yourself. If the offered cash is below that present value, you are being asked to sell your future income at a discount to what you could make on your own. Use the breakdown's annuity factor to sanity-check: very long streams should approach 1/r at low rates.
An $18,000-a-year defined benefit pension and a $1,500 monthly account-based pension payment are different calculations, because monthly cash starts earning immediately instead of waiting a year. Always set the frequency toggle to match the actual offer and enter the per-period payment. A monthly stream is worth slightly more than its annual-total equivalent at the same annual rate, purely because the money arrives earlier.
Many real streams are fixed in nominal dollars or only partly indexed — CSS pensions index fully to CPI, many annuities offer fixed or partial indexation, and account-based pension payments are whatever you withdraw. A fixed $18,000/year for 25 years loses purchasing power every year inflation runs above zero, which a constant discount rate understates. If the stream is not inflation-indexed, use a higher effective discount rate to reflect the erosion, and remember the tax treatment differs: DB pension income is generally taxed as income above age 60 thresholds, while account-based pension payments are tax-free from 60.
Linda was offered a $245,000 commutation or a $18,000-a-year indexed pension from her Commonwealth scheme. Running the present value at a conservative 5% over her expected payout years, the stream was worth more than the offer — and it came with longevity protection and CPI indexation the lump sum could not match. She kept the pension, knowing the numbers, not the sales pitch, had driven the choice.
Marcus was offered a 15-year monthly payout at an implied discount rate of 7.5% — far above what he could earn safely. Computing the present value at his own 5% opportunity rate showed the insurer's offer undervalued the stream, but he wanted the cash now to seed an account-based pension, so he negotiated the lump sum up closer to the computed present value before signing, adding meaningful money by simply quoting the number.
Anita was comparing two settlement offers, one annual and one monthly, both nominally equal. Modelling both at the same rate, the monthly offer came out several thousand dollars higher in present value because each instalment arrived earlier. The annual offer had looked identical on paper; the calculator revealed the difference the face values hid.
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Financial Chaos Analyst
Ivy Sinclair-Wren is a Financial Chaos Analyst covering investing, AI, wealth psychology, and the emotional consequences of opening finance apps during market crashes. Based in Melbourne, she specializes in demystifying the Australian tax code and helping users navigate the intersection of spreadsheet logic and human irrationality.