What is the Probability of Running Out of Money Calculator?
The Probability of Running Out of Money Calculator helps you understand how likely it is that your retirement savings could be exhausted during your lifetime. By modelling your pensions, investments, property income and spending across many possible market outcomes, it shows how robust your retirement plan really is.
This tool is designed for UK investors and retirees who want a clearer, more realistic view of retirement risk, rather than relying on a single average return assumption.
How the Calculator Works?
This calculator models your retirement year by year from your chosen retirement age to your target end age. It combines all your investment pots, including SIPPs, workplace pensions, ISAs and taxable accounts, with guaranteed income sources such as DB pensions, State Pension and buy-to-let property income.
You can run the model in two ways:
- Monte Carlo simulation, which generates thousands of possible market paths using realistic return and volatility assumptions
- Deterministic stress testing, which applies fixed return sequences such as poor early years or poor late years to highlight sequence of returns risk
The results show the probability that your money lasts for your full retirement, and the probability that it runs out before your chosen age.
All figures are shown in real terms, meaning today’s spending power after inflation.
Step One: Enter Your Retirement Assets and Income
Add your pension pots, ISAs, taxable investments, cash and any guaranteed income sources such as DB pensions, rental income and the State Pension.
Step Two: Set Your Spending and Time Horizon
Enter your planned retirement spending, retirement age and target end age. This defines the period during which the model tests your plan across.
Step Three: Review Probabilities and Stress Outcomes
See the probability that your money lasts your full retirement and the likelihood of running out early. Adjust spending, income or assumptions to improve resilience.
Probability of Running Out of Money Calculator
Also known as a Probability of Ruin Calculator in retirement planning.
Model your UK retirement drawdown plan across SIPPs, workplace pensions, ISAs, GIAs, DB schemes and buy to let property. See how likely you are to run out of money under different market paths.
Disclaimer: This calculator provides illustrative projections only and does not constitute financial advice. Investment returns, inflation and personal circumstances can vary significantly. Consider speaking with a qualified financial adviser before making major retirement decisions.
What does retirement mean to you?
Traditional retirement is broken. Understand how our calculator enables you to live a better life now vs later.
Retire from corporate work?
Use the tool to utilise how you can step away from the corporate world and live life on your own terms.
Work less, live more
See how part-time or project-based work can bridge your income gap while giving you more time for life.
Freedom through planning
Understand how your savings, spending and investments can work together to buy back your time.
Test-drive retirement early
Model scenarios that let you experience elements of retirement before fully stepping away.
What is the Probability of Running Out of Money Calculator?
It is a UK-specific retirement risk tool that uses probability modelling and stress testing to show how likely your savings are to last for your full retirement.
What does this calculator actually show?
It shows the probability that your retirement plan succeeds or fails. Instead of one outcome, you see a range of possibilities and how often your money lasts versus runs out.
Why is probability more useful than a single projection?
Real markets do not deliver smooth average returns. Sequence of returns, volatility and timing matter. Probability modelling reflects this uncertainty and gives a more realistic picture of risk.
What is Monte Carlo simulation?
Monte Carlo simulation generates thousands of possible future market paths using expected returns and volatility. Each path tests whether your money survives your full retirement.
What is deterministic stress testing?
Deterministic testing applies specific scenarios, such as poor returns early in retirement or prolonged low growth, to highlight vulnerabilities that averages can hide.
What investments does the calculator include?
It includes SIPPs, workplace pensions, ISAs, taxable accounts, cash and income from property. Guaranteed income, such as DB pensions and the State Pension are layered in separately.
Does this calculator include tax?
It works in real net terms. If tax meaningfully affects your plan, you can adjust spending or net income assumptions accordingly.
What probability should I aim for?
There is no universal answer. Many people feel comfortable with success probabilities above 85–90%, but the right level depends on flexibility, risk tolerance and backup options.
How accurate are the results?
They are scenario-based estimates, not predictions. Their value lies in showing risk exposure and helping you make better decisions under uncertainty.
Is my information stored?
No, all tools run client-side, and nothing is saved.
Is this a replacement for financial advice?
No. It is a planning and risk-awareness tool, not regulated advice.