Why A$20 is the practical minimum
A$10 sites exist, but A$20 is where most of the market begins. Card payments, many e-wallets and most vouchers work at that level, so you have more choice of how to pay and, importantly, how to get paid. Several of the casinos above also set their withdrawal floor close to A$20: Dolly about A$20, Mafia Casino A$20 and Level Up A$10. That symmetry matters more than it looks. A small win can actually leave the casino.
The bonus picture also changes. At A$10, almost no welcome offer applies. At A$20, a few offers may apply, so check the promotion terms at Level Up, Boho, Ricky and Richard, where our data has no separate bonus minimum; at A$30 you unlock SkyCrown, Dolly, SlotsGem and Mafia Casino. If you are deciding between A$20 and A$30, ask whether you want the bonus. A $20 deposit casino Australia players choose for a casual session is usually better used with cash; a A$30 deposit with a match and free spins suits someone planning several sessions.
Matching games to a A$20 balance
With A$20, the number of spins you get depends on the minimum bet. Many modern pokies start at A$0.20, giving about a hundred spins. Higher-volatility games such as Money Train 4 can go a long stretch without a feature, so a hundred spins may not be enough to see its bonus round; a gentler game will give you more back-and-forth. Sweet Bonanza 1000 sits in between: wins come from clusters of eight or more symbols, and the big multipliers are kept for the free spins.
A worked example
Deposit A$20 at Level Up and take the first welcome step if its terms apply to your deposit. If the match were 100%, you would hold A$40 with 40x wagering on the A$20 bonus: A$800 of bets inside 14 days. At A$0.40 a spin, that is 2,000 spins, and the expected cost on a 96% game is about A$32, more than the bonus itself. Without the bonus, your A$20 is free to play or withdraw at any point. Run the numbers for the actual match on offer before you opt in.