Drawdown Calculator NZ
This calculator works out how many years a retirement lump sum will last once you start drawing an income from it, so you can check whether your planned spending is sustainable or whether you are on track to run out of money. You enter your retirement lump sum, the amount you plan to withdraw each year in today's dollars, the expected annual return on your investments, and the rate of inflation. The calculator then steps through the numbers year by year, growing your balance by the expected return and subtracting your withdrawal, which it increases each year with inflation so your spending power stays the same throughout retirement. It returns three results: how long the lump sum lasts, your withdrawal expressed as a percentage rate of the starting balance, and the dollar amount of your first year's withdrawal. If your expected return comfortably covers your withdrawals, the balance can hold steady or keep growing, and the result shows the money lasting indefinitely instead of counting down to zero. Use it to test different withdrawal rates and compare against commonly cited guides such as a 4% rate. It leaves out tax and NZ Super, which is a separate income on top and can let your own savings stretch further, so treat the result as an indicative estimate, not financial advice.
Withdrawals rise each year with inflation to keep your buying power steady. If the return covers withdrawals, the savings can last indefinitely. This ignores tax and NZ Super, which is a separate income on top. Estimate only, not financial advice.
How it works
The calculator steps through each year, growing the balance by the expected return, then taking out your withdrawal, which it increases each year by inflation so your buying power stays steady. It counts the years until the balance hits zero. If the return comfortably covers the withdrawals, the balance holds or grows, and the result shows the savings can last indefinitely at that rate.
Worked example
A $500,000 lump sum with $30,000 a year withdrawals is a 6% withdrawal rate. At a 4% return with 2.5% inflation, the savings last around 20 years before running out. Dropping the withdrawal to $20,000, a 4% rate, would make the money last far longer or indefinitely.
Related calculators
- Retirement Calculator: plan for retirement.
- Annuity vs Drawdown Calculator: steady income versus drawdown.
- Real Return Calculator: return after inflation.
- KiwiSaver Provider Fee Comparison Calculator NZ 2026/27: 30-Year Cost.
- KiwiSaver Switch Break-Even Calculator NZ 2026/27: how many months of fee savings repay a KiwiSaver switch's cost or time.