purchased annuity calculator

What is a purchased annuity?

A purchased annuity is typically a contract where you hand over a lump sum to an insurer in exchange for a stream of future income payments. Depending on the product, those payments may be guaranteed for a fixed term, based on life expectancy, or include additional riders such as inflation adjustments or survivor benefits.

This calculator uses a fixed-term annuity framework so you can quickly estimate periodic income and total payout. It is a practical planning tool for retirement income, pension bridging, or cash flow comparisons against bonds and dividend portfolios.

How this purchased annuity calculator works

The model is based on the standard present-value annuity formula. You input:

• Purchase amount (your upfront premium)
• Expected annual rate (discount/return assumption)
• Payout period in years
• Payment frequency (monthly, quarterly, etc.)
• Payment timing (beginning or end of each period)

From there, the calculator estimates the periodic payment and breaks down total return of capital versus estimated interest component over the payout term.

Taxable portion estimate

Many jurisdictions treat annuity payments as part return-of-capital and part earnings. To help with planning, this tool approximates:

• Return of capital per payment = purchase amount ÷ number of payments
• Taxable portion per payment = payment − return of capital portion
• After-tax estimate = payment − (taxable portion × marginal tax rate)

Actual tax treatment varies by country, product type, and regulation. Always verify with a tax professional.

Formula used

For an ordinary annuity (payments at the end of each period):

Payment = PV × i ÷ (1 − (1 + i)^−N)

Where:

• PV = purchase amount
• i = periodic rate (annual rate ÷ payments per year)
• N = total number of payments (years × payments per year)

If payments occur at the beginning of each period (annuity due), the payment amount is adjusted lower for the same purchase amount because each payment arrives one period earlier.

Why this is useful for retirement planning

Purchased annuities are often used to convert savings into predictable income. A calculator like this helps you quickly test scenarios before talking to insurers or advisers.

• Compare monthly income from different lump sums
• See the impact of changing rates and term length
• Estimate after-tax cash flow for budgeting
• Understand the trade-off between income now and capital preservation

Example scenario

Suppose you contribute $150,000 into a 20-year annuity, with a 5.5% annual assumption and monthly payments. The calculator returns an estimated monthly payment, total expected payout over 20 years, and approximate taxable component per payment.

If you change the payment frequency to annual or quarterly, you will see how payout shape changes. If you switch from end-of-period to beginning-of-period payments, the periodic amount changes because the timing of cash flow changes the present value math.

Important limitations

• This is not a real insurer quote.
• Life annuities depend on age, sex, mortality tables, and underwriting.
• Fees, commissions, inflation riders, and guarantees are not explicitly modeled.
• Tax rules differ by region and contract structure.

Bottom line

Use this purchased annuity calculator to build intuition and compare options fast. For actual purchase decisions, get multiple insurer quotes and validate tax implications with a licensed professional.