How we Calculate EV & PSW for Casino Bonuses

Example Bonus Details

First Deposit 100% up to A$3,000 + 200 Free Spins

Deposit: A$3,000

Bonus: A$3,000 (100% match)

Free Spins: 200

Wagering Requirement: 50x bonus

RTP (Return to Player): 96% (wagering on slots only)

* For calculating EV (Expected Value) and PSW (Probability of Successful Wagering), it's best to assume an RTP of 0.96 by default—unless a specific RTP list is provided.

Expected Value (EV) Calculation

EV shows the average amount you can expect to win or lose from a bonus after completing the wagering. A positive EV means the bonus is potentially profitable in the long run.

Formula:

EV = (RTP × (Bonus + Deposit)) − Deposit

Calculation:

EV = (0.96 × (3,000 + 3,000)) − 3,000

EV = (0.96 × 6,000) − 3,000 = 5,760 − 3,000 = A$2,760

Probability of Successful Wagering (PSW) Calculation

PSW estimates your chances of completing the wagering requirement before running out of money. The higher the PSW, the better your odds of turning the bonus into real cash.

Formula:

PSW = exp(−(W × (1 − RTP)) / (Bonus + Deposit))

Where:

W = Bonus × Wagering = 3,000 × 50 = 150,000
RTP = 0.96
Bonus + Deposit = 6,000

Calculation:

PSW = exp(−(150,000 × 0.04) / 6,000)

PSW = exp(−1) ≈ 0.3679 or 36.8%

Why Slots Are the Primary Tool for Wagering Bonuses

100% Contribution to Wagering
Most online casinos count slot wagers at 100% toward the wagering requirement. In contrast, games like roulette, blackjack, and baccarat typically contribute only 5–20%—and sometimes not at all.
High RTP on Slots
Many slots have a Return to Player (RTP) of 96–97%, which makes them suitable for minimizing losses during wagering.
Autoplay Functionality
Autospins allow players to automate the process, making it easier and faster to complete the wagering requirement.
Wide Selection
Casinos often offer hundreds of slots, usually without restrictions. This gives players the freedom to choose those with the highest RTP.

But Keep in Mind

Not all slots are eligible for bonus wagering—some high RTP or jackpot games may be excluded.
A maximum bet rule is often in place (e.g., you can't bet more than $5 per spin).
Some casinos intentionally select lower RTP slots for bonus wagering, if the game provider offers multiple RTP versions.

Real-World Limits That Affect Wagering

While EV and PSW are based on math, real-world conditions often reduce your actual chances of success.

Maximum Bet Rule

Let’s say the bonus has a maximum bet limit of $5. To complete a A$3,000 bonus with 50x wagering:

Total wagering required: 3,000 × 50 = A$150,000
At $5 per spin: 150,000 / 5 = 30,000 spins

Time Limit Example

Now suppose you only have 3 days to complete wagering, and you're using slots:

Slots average: ~25 spins per minute
That’s 1,500 spins per hour
You’ll need: 30,000 / 1,500 = 20 hours of spinning within 3 days!

That’s very demanding, especially for casual players.

Table Games = Slow Progress

If you try to complete the bonus using live games (like roulette or blackjack), most casinos only count 5–10% of your wagers. That means you’d need 10–20× more time and money — basically, impossible within the deadline.

Withdrawal Cap

Some bonuses have a withdrawal limit, for example: “Max cashout = 5x bonus”. This means:

Even if you win more, you can’t withdraw beyond the cap, which makes high EV misleading in such cases.

Summary and Final Tip

EV tells you how much profit you can expect mathematically.
PSW tells you how likely you are to finish wagering.
But... real limits like max bet, time constraints, low contribution rates, and cashout caps may drastically lower your actual chances.