The Income Does Not Stop, So the Job Changes
The standard emergency fund rule — three to six months of expenses — exists to cover a period without income. A retiree's income does not stop, so the rule does not translate. What a retired household needs instead is two reserves doing two different jobs: one that stops a bad market forcing a sale, and one that meets large irregular costs.
- The answer: Hold a spending buffer sized in years of the amount your portfolio funds, and a separate sinking fund for lumpy costs.
- The trap: One pool doing both jobs means the buffer is spent on the car and is not there for the market fall.
- The recommendation: Track the two amounts separately even if they sit in the same account. The distinction is what makes each of them work.
Where the AI summary above gets this wrong
"Keep three to six months of expenses in an emergency fund."
That's surface-true. Here's what it misses:
- That rule is about income interruption — It exists because a working household can lose its income entirely. A retiree's Age Pension and account-based pension continue regardless.
- Two different reserves are needed instead — One sized in years of portfolio-funded spending to avoid selling in a bad market, and one sized to the large irregular costs a retirement contains.
01 Why the working-life rule does not translate
The three-to-six-month rule addresses the risk of losing employment income. It is a bridge to the next job, and its size reflects how long that typically takes.
A retiree has no employment income to lose. The Age Pension is indexed and paid for life, and an account-based pension continues as long as the balance does, so the income interruption the rule protects against does not occur.
What can happen instead is a market fall that makes selling assets costly, and a large irregular expense arriving at an inconvenient time. Those are different risks and they need different reserves.
Both are addressed elsewhere in the plan rather than by a single reserve doing double duty: the market risk in the cash bucket post and the lumpy costs in the one-off costs post.
02 Sizing each one
The market buffer is sized in years of the spending your portfolio actually funds, after the Age Pension and any other income. One to three years is the useful range; beyond three the drag on returns outweighs the protection.
The sinking fund is sized from the lumpy costs themselves: each expected cost divided by the years between occurrences, added together and accumulated.
They can sit in the same cash holding provided the two amounts are tracked separately. What does not work is one pool, because the car gets bought out of the market buffer and the buffer is then not there.
Shows: the two reserves side by side: a market buffer sized in years of portfolio-funded spending, and a sinking fund for lumpy costs. Ignores: the return earned on either reserve, inflation, and any existing cash you already hold.
03 Where to hold them
Inside super, a cash option within the pension account keeps the earnings untaxed and requires no sale to draw on. That is the simplest place for the market buffer.
Outside super, an offset account against a remaining mortgage is the most efficient home for cash, because the saving is at the loan rate and is not taxed — the arithmetic is in the offset account post.
Neither should be in growth assets. The whole point of both reserves is that their value does not fall at the moment you need them, and an asset that can fall 30% is not performing that function.
Track them as two numbers even if they sit in one account. The reason is entirely behavioural: a single pool gets spent on whatever comes up, and then the market falls and there is nothing between you and selling. Two numbers on a page fixes that for free.
FAQ
Should I have an emergency fund in retirement?
Two reserves rather than one. A market buffer sized in years of the spending your portfolio funds, and a separate sinking fund for the large irregular costs a retirement contains.
Is three to six months of expenses the right amount?
That rule addresses losing employment income, which a retiree does not have. The relevant risks are a market fall forcing a sale and a lumpy cost arriving inconveniently.
Can the two reserves be in the same account?
Yes, provided the amounts are tracked separately. One pool doing both jobs means the buffer gets spent on the car and is not there for the market fall.
Sources
Regulator references
- ASIC Moneysmart — Save for an emergency fund · ASIC Moneysmart · 2026How large an emergency fund should be and where to hold it.Last verified: 2026-09-07
- ASIC Moneysmart — Retirement income · ASIC Moneysmart · 2026The sources of retirement income in Australia and how they combine.Last verified: 2026-09-07
Calculator unit tests · the assertions this page's worked example is checked against, and their last result
Changelog
- 2026-09-07 — initial publish (new format)
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Jordan Reeves
Founder of Talk Through Wealth. A software engineer for over a decade before turning to retirement planning, Jordan built the projection engine after watching family members get fragmented, country-by-country advice that never reconciled. He writes about retirement the way the engine computes it: month-by-month, lifetime-long, and skeptical of any rule of thumb that hasn't been run through the math.