What it means
The mechanics are straightforward. You pay a single premium, choose when payments start, and the insurer calculates an amount based on your age, gender in some markets, prevailing interest rates and the options you select.
Payments then arrive monthly, quarterly or annually for as long as the contract specifies. Two timing choices define the product.
An immediate annuity begins paying within about a year of purchase, while a deferred income annuity is bought earlier and starts paying at a chosen future date, which produces a much larger payment for the same premium because the insurer holds the money longer. Some buyers use a deferred contract starting at age 80 or 85 purely as insurance against living a very long time.
The options attached to a contract change the payment materially. A single life annuity pays the most but stops at death; a joint life contract continues to a surviving spouse at a reduced level; a guarantee period pays to your estate if you die early; and an inflation-linked option starts lower but rises each year.
Every protection you add reduces the starting income, because the insurer is taking on more risk. The core benefit is removing longevity risk from the individual and giving it to the insurer, which can pool thousands of lives.
That pooling is why an annuity can pay more than a cautious investor could safely withdraw from the same pot alone. The cost is irreversibility, since in most cases the capital cannot be recovered once payments begin.
Interest rates drive pricing more than anything else. Annuity payments are largely a function of the yields the insurer can earn on long-dated bonds, so the same $500,000 buys noticeably more income when rates are high than when they are low.
This is why timing and, for larger sums, staggering purchases across several years are worth considering.
In practice
Real-world examples.
Example
A retiring teacher has $400,000 in pension savings and fixed monthly costs of $2,800. She annuitises $250,000 to cover her essential bills for life and keeps $150,000 invested for holidays and emergencies. The split means a market downturn cannot touch her rent or utilities.
Example
A couple in their early sixties buy a joint life annuity with a 10-year guarantee period. The starting income is lower than a single life contract would pay, but the survivor keeps receiving payments and their children receive the remaining guaranteed payments if both die within a decade.
Example
A 60-year-old with a large portfolio buys a deferred income annuity that starts paying at 85 for a modest premium. It costs little now because payments may never begin, and it lets him spend his other savings more freely up to that age knowing a floor exists behind it.
Formula
Calculation
Annual income = Premium x Payout rate, where the payout rate is set by the insurer based on age, contract type and prevailing interest rates.
A 68-year-old buys a single life immediate annuity with a $500,000 premium at a quoted payout rate of 6%. Annual income is $500,000 x 0.06 = $30,000, which is $30,000 / 12 = $2,500 per month for life.
A useful sense check is the simple payback period: $500,000 / $30,000 = 16.7 years, so the buyer recovers the premium in nominal terms at about age 85 and everything after that is the insurer's risk. Adding a joint life option for a spouse might reduce the rate to 5.2%, giving $500,000 x 0.052 = $26,000 a year, or $2,166.67 per month, that continues to the survivor.Case study
Seen in the real world.
Bramblewood Foundry is an invented business used here as an illustrative example. Its founder sold the company at 66 and held $1.2 million from the sale, most of it in a balanced investment portfolio, and worried that a bad first decade of returns would force him to cut spending permanently.
Working with an adviser, he used $450,000 to buy an immediate annuity paying 6.2%, or $27,900 a year, which together with his state pension covered his essential household costs. The remaining $750,000 stayed invested for discretionary spending and for his children.
In this illustrative scenario a market fall of 20% two years later reduced his portfolio but changed nothing about his ability to pay the bills. He described the annuity afterwards as the part of the plan that let him stop watching the markets every morning.
Watch out
Common mistakes.
- Annuitising the entire retirement pot. Most planners suggest covering essential fixed costs with guaranteed income and keeping the rest invested for flexibility and emergencies.
- Comparing quotes on headline income alone. A higher payment often reflects fewer protections, such as no spousal continuation, no guarantee period and no inflation increases.
- Assuming the income keeps its purchasing power. A level annuity pays the same cash amount for decades, which at 3% inflation loses roughly a quarter of its real value in ten years.
Questions
People also ask.
Can I change my mind after payments start?
Generally no, since income annuities are irreversible once the payout phase begins, which is why the decision needs care up front.
What happens to the money if I die early?
Nothing goes to your estate under a plain single life contract, which is why guarantee periods and joint life options exist.
Do interest rates really matter that much?
Yes, payout rates track long-term bond yields closely, so the same premium can buy substantially different income depending on when you buy.
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