Stress testing your retirement plan: modelling catastrophic scenarios to build resilience

For most pre-retirees and retirees, the central question about a retirement plan is whether it will work — whether the money will last, whether the income will be adequate, whether the assumptions underlying the plan are reasonable. The standard answer involves modelling expected outcomes: average investment returns, average longevity, expected expenses. That analysis is necessary and useful. But a retirement that spans 25 to 35 years rarely unfolds as a series of average outcomes, and a plan that works under normal conditions may fail under abnormal ones. Stress testing asks the harder question: if specific adverse scenarios occur, does the plan still hold up? And if it does not, what can be done about it now?

This is not a pessimistic exercise. In practice, most well-constructed retirement plans survive most stress scenarios, particularly when specific mitigants are in place. Stress testing identifies plan strengths, reveals where specific vulnerabilities exist, suggests practical protective measures, and ultimately produces greater confidence in the plan. The goal is not to find reasons for anxiety — it is to find reasons for robustness.

Scenario 1: Major market crash in early retirement

The single most consequential stress scenario for most retirees is a significant market fall in the first three to five years of retirement. The mechanism is sequencing risk: the combination of a large market decline with continued withdrawal of income for living expenses creates a lower portfolio base from which to recover. Consider a $1 million portfolio drawing $50,000 per year for living expenses. In year one, a 30% market fall reduces the portfolio to $700,000; after the year's income withdrawal, it stands at $650,000. In year two, without a market recovery, the same $50,000 drawdown leaves $600,000. The portfolio is now at $600,000 against an expected trajectory of $900,000 or more — and the shortfall is permanent unless investment returns significantly outperform averages for an extended subsequent period.

The practical mitigants are well-established. A cash buffer of two to three years of expected expenses, held outside the growth portfolio, allows a retiree to draw on cash during a market crash and let growth investments recover undisturbed. A variable drawdown strategy — reducing living withdrawals during down markets and increasing them during strong markets — significantly extends portfolio longevity over most market sequences. An explicitly more conservative investment allocation in the first five to ten years of retirement — somewhat more defensive, somewhat less equities — reduces the depth of potential drawdowns during the highest-risk period. None of these measures eliminates the risk; all of them reduce it.

Scenario 2: Sustained low returns

The market crash scenario involves a sharp decline; this scenario involves sustained disappointment. If investment returns average one to two percent in real terms over a decade rather than the four to five percent that historical data suggests, a plan built on historical averages faces material strain. This scenario is not far-fetched: Japan has experienced decades of low returns, and sustained high valuations in some global markets have raised concerns about future expected returns.

The practical response is to build the plan on conservative return assumptions rather than historical averages, to have a credible fallback strategy (part-time work for those who are able, downsizing, and for those eligible, the Age Pension as a base-level backstop), and to avoid committing to an expenditure level in early retirement that leaves no room for adjustment.

Scenario 3: Longevity to 100 or beyond

Retirement planning typically uses an assumed planning horizon of age 85 to 90. For couples, the question is how long at least one of the two will live, and the statistics suggest that for couples currently in their mid-60s, planning to at least 95 for at least one partner is appropriate — the top 10 to 20 percent of the current retirement cohort will live well into their 90s or beyond.

A plan designed to last to 90 that must actually sustain a further ten or more years faces a substantial additional drawdown burden. The primary practical mitigant is a guaranteed income layer: a lifetime annuity purchased with a portion of retirement savings provides income regardless of how long the retiree lives, removing the longevity risk from that portion of the plan entirely. For those who remain eligible, the Age Pension also functions as a longevity backstop — an indexed income floor that continues regardless of how long the recipient lives. Conservative drawdown rates — drawing a smaller percentage of assets each year — preserve capital for extended retirement without requiring the certainty of an annuity.

Scenario 4: Major healthcare event

A cancer diagnosis, a significant accident, or the onset of dementia creates out-of-pocket healthcare costs that a standard retirement plan may not explicitly anticipate. For retirees, the financial impact depends on the severity and duration of the condition, the level of private health insurance held, and whether residential aged care eventually becomes necessary.

The planning mitigants include maintaining appropriate private health insurance (which covers hospital and some specialist costs), understanding the PBS Safety Net that reduces out-of-pocket drug costs for high medication users, maintaining an emergency reserve separate from the regular retirement portfolio, and having completed aged care financial planning that accounts for potential means-tested care fees. The aged care means-tested care fee has an established lifetime cap (though that cap figure should be confirmed at myagedcare.gov.au, as the 2024-25 reforms changed fee structures), which provides certainty about the maximum financial exposure from that source.

Scenario 5: Family support demands

Adult children face financial crises: marriage breakdowns, business failures, housing pressure, medical events. Grandchildren have special needs. A parent in another country needs financial assistance. Family dynamics place financial demands on retirees that a standard retirement plan does not model.

This scenario is less amenable to structural financial solutions than the others. Clear family communication about the retiree's financial position — what is available for support and what is not — provides better protection than any financial product. A specific reserve earmarked for family contingencies, separated from the core retirement portfolio, can contain the impact. And integrated estate planning that is clear about what will and will not be provided to family during life, as well as what will be left at death, removes ambiguity.

Scenario 6: Death of the spouse

For a couple, the death of one partner produces a cascade of financial changes: Centrelink transitions the survivor to single rates; the survivor may lose one of the superannuation pension streams; estate administration and the bereavement period require active management. The survivor's income is lower, but their fixed household expenses — housing, utilities, most ongoing costs — do not halve. The financial gap can be meaningful.

Reversionary pensions, which continue paying to the surviving partner after the primary pensioner's death, address the superannuation income gap. Adequate life insurance (for those who still hold it in pre-retirement years) can provide a capital injection. Clear estate planning ensures that assets flow to the survivor promptly and without the friction of administration delays. And Centrelink's bereavement payment and the transition to single rates are both time-sensitive processes that the survivor or their support network needs to navigate — prompt notification to Centrelink within 14 days is a legal obligation.

Doing the work

For most retirees, a constructive approach to stress testing involves identifying the two or three scenarios most relevant to their specific circumstances — given age, health, family composition, asset level, and whether they receive the Age Pension — and modelling each one specifically. Most financial advisers have access to specialist modelling software that can run hundreds or thousands of different market scenarios to show the probability that a given plan succeeds across different conditions. For retirees managing their own affairs, a spreadsheet that applies specific shock scenarios — a 30% year-one return, ten extra years of life, a $100,000 healthcare event — provides a less sophisticated but still useful picture of plan robustness.

The most important outcome of stress testing is not a single number or probability. It is the conversation about what the mitigants are — what specific actions, products, or structural choices reduce the likelihood that each adverse scenario breaks the plan. A retirement plan with identified mitigants for its key vulnerabilities is a more robust plan than one that has simply avoided stress testing its assumptions.

Sources

• Age Pension — Services Australia
• Annual and lifetime caps for your aged care costs — Services Australia
• PBS Safety Net thresholds — Services Australia
• Lifetime income streams — Moneysmart
• Account-based pensions — Moneysmart
• What help there is when an adult dies — Services Australia