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Regular investing in Australia: inside and outside super

The biggest regular investment most Australians make happens automatically: your employer must pay at least 12% of your ordinary earnings into super (ATO). Enter that as the monthly amount here to see what the guarantee alone could grow to.

On top of that you can salary sacrifice into super, where contributions are generally taxed at 15% in the fund instead of your marginal rate — but the money is preserved until you reach preservation age and meet a condition of release, and annual contribution caps apply. Investing outside super keeps the money accessible, but earnings are taxed at your marginal rate along with your other income.

The choice is usually access versus tax: money for a home deposit or the next decade belongs outside super; money for retirement benefits from the lower tax inside it.

There is one bridge between the two: the First Home Super Saver scheme lets first-home buyers release eligible voluntary contributions, and their earnings, from super to put towards a deposit — so saving for a first home can still use super's lower tax. Limits and conditions apply; check them with the ATO before relying on it.

Worked example: What the super guarantee alone can build

On a $90,000 salary, the 12% guarantee is $10,800 a year — $900 a month. At an illustrative 6% a year for 30 years, before fees and contributions tax:

• You pay in $324,000.
• It could grow to about $881,300 — roughly $557,300 of growth on top of what you put in.

Change the amount, return or years in the calculator above to test your own version; try a lower return too, because none of these is guaranteed.

How compounding builds wealth

Returns start earning returns of their own: a lump sum grows by FV = PV × (1 + r)ⁿ, and a regular contribution by FV = P × [ ((1 + r)ⁿ − 1) / r ] × (1 + r), where each payment compounds for as long as it stays invested. The earliest contributions do most of the work, which is why starting early matters more than starting big.

Lump sum or monthly — which ends up ahead?

Switch between the two modes and the answer is consistent: for the same total contributed, a lump sum wins, because every unit of money is invested for the full horizon rather than for an average of half of it. Take $324,000 at a 6% expected return over 30 years:

• All at once — $324,000 invested on day one grows to roughly $1,861,000.
• $1,000 a month for 30 years — the same $324,000 contributed, ending at roughly $881,000.

A $980,000 gap, purely from time in the market — but the comparison is usually hypothetical. If you don't have $324,000 today, the real choice is $1,000 a month or nothing, and $881,000 beats nothing. Monthly investing also spreads your entry over 360 different prices instead of betting everything on one day.

Where the money to invest comes from

Start from what survives tax, not your salary. Work out your monthly take-home pay, subtract what you genuinely spend, and use what's left — the whole result depends on not stopping.

Tips and common mistakes

• Check your super is actually being paid. Your fund statement or myGov shows each employer contribution.
• Mind the caps. Salary-sacrificed contributions count toward an annual concessional cap — check the current figure with the ATO before sacrificing a large amount.
• Look at your fund's investment option. Default balanced options and high-growth options assume very different long-run returns — set the rate above to match.
• Be realistic about returns. Model a conservative rate as well as an optimistic one — real returns vary and can be negative in any year.
• Compare it against paying down debt. The interest a loan overpayment saves is a guaranteed return, which an expected 10% is not.