Coast FIRE Australia: How to Calculate Your Number and What to Do Once You Hit It

Coast FIRE is the point where you've saved enough that compound growth will do the rest — you could stop contributing to your investments entirely and still reach full financial independence by your target retirement age.

Once you hit your Coast FIRE number, you're not retired. But you're free. You only need to earn enough to cover your current living costs. No more aggressive saving, no more forcing yourself to invest 50% of your pay cheque. You can coast.

For Australians, calculating Coast FIRE is more complex than it looks — because super is locked until 60, you actually need two Coast FIRE numbers, not one.

What Coast FIRE means

Think of it this way: your invested portfolio earns returns every year. If you leave it alone long enough, it doubles every 7–10 years (depending on returns). Coast FIRE is the moment when your existing portfolio is already "pre-loaded" with enough momentum to reach your FIRE number by a target retirement date — with no further contributions.

Formula:

Coast FIRE Number = FIRE Number ÷ (1 + annual return rate)^years until target retirement

Example:

• Your FIRE number (annual expenses × 25): $1,500,000
• Current age: 35
• Target retirement age: 60 (25 years away)
• Expected annual return: 7%

Coast FIRE Number = $1,500,000 ÷ (1.07)^25 = $1,500,000 ÷ 5.43 = $276,400

This means if you have $276,400 invested at age 35 and never contribute another dollar, it will grow to $1.5 million by age 60 at a 7% return. Once you hit $276,400, you've hit Coast FIRE.

Use our Coast FIRE Calculator to find your exact number based on your age, current balance, and target retirement date.

The Australian super complication

In Australia, you can't access super until preservation age (60 for most people). This means a standard Coast FIRE calculation doesn't quite work — you need to separate your super and non-super money.

You actually need two Coast FIRE numbers:

1. Super Coast FIRE number How much do you need in super right now for it to grow into enough to fund retirement from age 60 onward?

2. Bridge fund Coast FIRE number How much do you need in non-super investments right now for it to grow to cover your lifestyle from your early retirement date until age 60?

Worked example: two-part Coast FIRE at 36

The scenario:

• Current age: 36
• Target early retirement age: 52
• Preservation age (super access): 60
• Annual expenses: $65,000
• Expected investment return: 7%/year

Step 1: Total FIRE number $65,000 × 25 = $1,625,000

Step 2: Split by phase

• Phase 1 (ages 52–60): 8 years of bridge fund
• Phase 2 (ages 60+): super takes over

Approximate portfolio split at retirement (age 52):

• Bridge fund needed at 52: ~$520,000 (to cover 8 years at $65k/year while letting super grow)
• Super needed at 52: ~$1,105,000 (to fund retirement from 60 at 4% withdrawal after 8 more years of growth in super)

Step 3: Back-calculate to today (age 36, 16 years away)

• Bridge fund Coast FIRE number = $520,000 ÷ (1.07)^16 = $520,000 ÷ 2.95 = $176,300
• Super Coast FIRE number = $1,105,000 ÷ (1.07)^16 = $1,105,000 ÷ 2.95 = $374,600

Combined Coast FIRE target at age 36: ~$550,900

If you currently have $176,300 outside super and $374,600 in super at age 36, you've hit Coast FIRE — you can stop contributing to your investments and still retire at 52.

What the numbers look like at different ages

How much you need in super and outside super to hit Coast FIRE, assuming $65,000 annual expenses and 7% return:

Current age	Target retirement	Super needed today	Bridge fund needed today	Total today
30	55 (25 years)	~$285,000	~$145,000	~$430,000
35	55 (20 years)	~$405,000	~$205,000	~$610,000
40	55 (15 years)	~$575,000	~$290,000	~$865,000
30	60 (30 years)	~$200,000	~$100,000	~$300,000
35	60 (25 years)	~$285,000	~$145,000	~$430,000

Illustrative figures assuming 7% annual return and $65,000 annual expenses. Super balance projections don't account for ongoing SGC contributions.

Note that ongoing employer super contributions still help after hitting Coast FIRE. Your employer continues paying 12% SGC regardless, so super keeps being topped up — it just means your own additional contributions are no longer required.

How Coast FIRE is different from full FIRE

	Coast FIRE	Full FIRE
Portfolio at the goal point	Enough to grow to your target by retirement	Already at your full FIRE number
Work required after?	Yes — cover current living costs only	No — investments cover everything
Timeline to goal	Shorter (10–15 years for many)	Longer (15–30 years for most)
Pressure to save aggressively?	Drops significantly once reached	Continues until full FIRE number hit
Flexibility	Work part-time, take a career break, go self-employed	Fully optional work

What do you do after hitting Coast FIRE?

This is where Coast FIRE becomes genuinely life-changing. Once your investments are "coasting" to your retirement target, you have several options:

Shift to a lower-stress job. Earnings only need to cover your current expenses, not fund savings. A stressful corporate role can become a part-time or lower-paying role you actually enjoy.

Take a career break. With your long-term future secure, a gap year or sabbatical isn't the financial catastrophe it would be earlier in life.

Change careers into something meaningful. Teachers, non-profit workers, artists, tradespeople — many careers pay enough to live on, just not enough to also save aggressively. Coast FIRE unlocks these options.

Start your own business. Without needing the business to immediately fund retirement savings, lower-risk entrepreneurship becomes viable.

Focus on the bridge fund. If you hit your super Coast FIRE number but haven't reached your bridge fund target yet, you might continue investing heavily in non-super assets while reducing the urgency of the whole thing.

Coast FIRE vs Barista FIRE

Coast FIRE and Barista FIRE are sometimes confused — here's the key difference:

• Coast FIRE: You've already saved enough that compound growth will do the rest. You earn enough to cover current expenses only.
• Barista FIRE: You've partially reached your FIRE number. Investments cover most of your expenses, and part-time work covers the rest. The portfolio doesn't need to keep growing dramatically — it supplements income.

In practice, many people pass through Coast FIRE on the way to Barista FIRE, and through Barista FIRE on the way to full FIRE. They're points on a continuum, not binary destinations.

Frequently asked questions

What is Coast FIRE in Australia?

Coast FIRE is the point where your current investments are large enough that compound growth alone will fund your retirement by your target age — with no further contributions needed. In Australia, this requires a two-part calculation because super is preserved until age 60: you need a Coast FIRE number for super and a separate one for your non-super (bridge fund) investments.

How do I calculate my Coast FIRE number?

The formula is: Coast FIRE Number = Full FIRE Number ÷ (1 + annual return)^years until target retirement. Your full FIRE number is annual expenses × 25. For Australians, you split this into super and non-super components and calculate each separately, since they become accessible at different times.

What return rate should I use in my Coast FIRE calculation?

Most Australians use 7% per year (the approximate historical nominal return from a diversified Australian/international equity portfolio). Some use 5% real return (after inflation) to be conservative. The higher the assumed return, the lower your Coast FIRE number — so conservative investors should use a lower rate.

Can employer super contributions count toward my Coast FIRE number?

Yes — employer SGC contributions (currently 12% of ordinary earnings) continue regardless of what you choose to do with your savings. Even after hitting Coast FIRE, employer contributions continue flowing into your super, which is an additional tailwind. Your own salary sacrifice contributions become optional.

What happens to Coast FIRE if my super can't be accessed until 60?

This is why Australian Coast FIRE requires two calculations — one for the super pool (accessible from 60) and one for the bridge fund (investments outside super that fund your life between early retirement and 60). The bridge fund calculation is typically smaller because it only needs to last until super kicks in.

Is 7% a realistic return assumption for Coast FIRE planning in Australia?

Over the long term (20–30 years), a diversified Australian/international equity portfolio has historically returned 7–10% nominally per year. However, past returns don't guarantee future results. Most financial planners use 6–7% for long-term projections, with 5% as a conservative figure. Using a lower assumed return gives you a larger (more conservative) Coast FIRE target.

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This article is for general information only and does not constitute financial, tax or legal advice. Individual circumstances vary. Consult a registered tax agent or licensed financial adviser before making decisions based on this information.