Paroli is a positive progression system: you double your bet after each win, then return to one unit after three straight wins or after any loss. Think of it as a reverse Martingale with a cap (some people call it the Anti-Martingale), and it dates back to the 16th century. Roulette is where most people try it, but you can apply the same rules to blackjack, craps and Sic Bo too.
Take a €200 bankroll (40 units) and a €5 unit. Each run of bets is called a cycle, and it ends after a loss or three wins in a row:
- Win three in a row and you stake €5, €10 and then €20, finishing €35 up.
- If the first bet loses, you're €5 down, and the next cycle starts again at €5.
- A win or two followed by a loss still leaves you €5 down overall.
These are worked examples to show how a cycle runs, and they say nothing about what you'll actually win. The house edge stays the same, no matter which staking plan you use.
How Do You Use the Paroli System?
The Paroli system only works on even-money bets, which pay out an amount equal to your wager (a 1:1 payout). In roulette, that means red or black, odd or even and high (19-36) or low (1-18).
First, you need to decide on a unit. This is the fixed amount you'll use as your base bet, and it should be something your bankroll can handle over a long session (the tips below cover sizing). The steps are:
- Each cycle begins with you betting 1 unit on any of the even-money betting options
- Double the bet amount after every winning bet
- Reset your bet amount to 1 unit after winning three bets in a row
- Return your bet to 1 unit after every losing bet
When you double, you're staking the money you just got back plus the winnings from that bet, so you don't add new money during a streak. That's why a loss after a win only leaves you 1 unit down in total. With a €5 unit, your largest single bet would be €20, but the most one cycle can cost you is €5. Each cycle risks 1 unit for a chance of winning 7.
Possible Results of a Paroli Cycle
The Paroli system capitalises on winning streaks while keeping bets low during losses. That means it only pays off when wins arrive in a row, and because each spin is independent, there is no guarantee that they will.
Think of play in cycles of up to three bets. The cut-off after the third win banks your profit and stops you from doubling stakes indefinitely, which could end in a severe loss. Below is every possible run of three bets, starting from 1 unit, with stakes and results in euros for a €5 unit:
| Bet 1 | Bet 2 | Bet 3 | Stakes (€5 unit) | Net result (units) | Net result (€) |
|---|---|---|---|---|---|
| Loss | Loss | Loss | €5, €5, €5 | -3 | -€15 |
| Loss | Loss | Win | €5, €5, €5 | -1 | -€5 |
| Loss | Win | Loss | €5, €5, €10 | -2 | -€10 |
| Loss | Win | Win | €5, €5, €10 | +2 | +€10 |
| Win | Win | Win | €5, €10, €20 | +7 | +€35 |
| Win | Loss | Win | €5, €10, €5 | 0 | €0 |
| Win | Loss | Loss | €5, €10, €5 | -2 | -€10 |
| Win | Win | Loss | €5, €10, €20 | -1 | -€5 |
Please note: these are examples, not predictions. Real results depend on luck, and on a real wheel, some of these outcomes are more likely than others.
As the table shows, five of the eight possible runs end in a loss. On the other hand, a successful streak wins you seven times your first winning bet.
At fair 50/50 odds, the eight results add up to exactly zero, so the five losses are balanced out by the +7 and +2 outcomes.
A real wheel tips that balance. The green zero makes three wins in a row less likely than the 12.5% you'd get at fair odds, so the big +7 outcome arrives less often. The next section has the numbers for each wheel.
Paroli Odds and House Edge: European, American and French Roulette
The wheel you play on sets the house edge. These are the three most common even-money setups:
| Wheel | Even-money bet wins | House edge | Three wins in a row | Expected loss per €1,000 staked |
|---|---|---|---|---|
| European (one zero) | 48.65% | 2.70% | 11.5% | about €27 |
| American (0 and 00) | 47.37% | 5.26% | 10.6% | about €53 |
| French with La Partage | 48.65% | 1.35% | 11.5% | about €14 |
Disclaimer: These are long-run averages, not predictions for a single session. On any given day, you could lose more, lose less or even win. No staking plan, Paroli included, changes the house edge, so only stake what you can afford to lose.
The win chances come from 18 winning numbers out of 37 on a European wheel and 18 out of 38 on an American one. At fair odds, you'd win 50% of spins and hit three wins in a row 12.5% of the time, with no house edge.
La Partage is a rule you'll find on some French roulette tables: when the ball lands on zero, you get half your even-money stake back instead of losing it all. You win just as often as before, but the loss on zero is cut in half, which brings the house edge down from 2.70% to 1.35%. Not every casino offers it, so look at the table rules before you sit down.
Paroli Compared With Other Betting Systems
Two things set Paroli apart from most other betting systems: the cut-off after three wins, and the fact that stakes go up after a win rather than a loss. That makes it less risky than aggressive systems such as Martingale, and it doesn't need as big a bankroll.
Martingale
Martingale is an aggressive betting system that focuses on recovering money lost on earlier bets. You double your stake after each loss, and like Paroli, it only suits even-money bets. Unlike Paroli, there's no cut-off point, so a losing streak can get very costly.
Say you stake 1 unit. If you lose five bets in a row, your next stake has to be 32 units. That's extremely risky, but the logic is that one win would recoup everything lost in the streak, no matter how long it goes on.
So Martingale doesn't capitalise on wins. It aims to recover losses, which means chasing them with ever-larger stakes. Table limits can also stop the progression before a win arrives.
Parlay
Parlay is used loosely. Some guides treat it as another name for Paroli, and others describe a version where you reinvest only part of your winnings, which is more conservative. In sports betting, "parlay" is also the term for an accumulator, so check which meaning a source has in mind.
Fibonacci
Fibonacci is another system that only applies to even-money bets. The Fibonacci sequence you see in nature and art has also been applied to gambling. Each number is the sum of the previous two. The sequence carries on forever, but it begins like this:
0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144
Start at any number in the sequence, from the second 1 onwards. Go up the sequence by one number after a losing bet and down by two after a winning bet. Bet 13 units, for example, and a loss means staking 21 next, while a win means staking 5. Like Martingale, it raises stakes after a loss to recover losses, so a long losing run gets expensive.
D'Alembert
The D'Alembert system also focuses on even-money bets. First, calculate 1% of your total bankroll, which becomes your baseline stake. Starting at 5 units (5% of your bankroll), each losing bet adds another unit to your next stake, and each win subtracts a unit.
Three wins and a loss would therefore leave your next stake at 3 units. Your stake never drops below 1 unit. Going up or down by just 1 unit keeps stakes lower than the doubling systems. It still raises your stake after losses, though, and it still can't beat roulette.
Paroli System Variants
Paroli has a few variants. They all follow the same basic idea, but some change how many wins you play for, and one reverses the direction altogether. The table below compares them using a €5 unit:
| Variant | Stake sequence (€5 unit) | Raise your stake after | You reset or stop | Full-streak result |
|---|---|---|---|---|
| Classic Paroli (three-win cap) | €5, €10, €20 | a win | after three wins or any loss | +€35 |
| Extended Paroli (four-win cap) | €5, €10, €20, €40 | a win | after four wins or any loss | +€75 |
| Contra Paroli (inverted) | €5, €10, €20, €40 and so on | a loss | after any win | a win recovers the losses plus €5 |
| Reverse Martingale | €5, €10, €20, €40 and so on | a win | after any loss | grows with the streak, and the loss that ends it leaves you €5 down |
Please note: none of these variants changes your odds, and every one of them can lose.
Classic Paroli (three-win cap)
This is the version covered in the rules above: double after each win, bank the profit after three, and go back to 1 unit after any loss. With a €5 unit, a full streak pays €35.
Contra Paroli (inverted)
Contra Paroli (sometimes called inverted Paroli) is the opposite way round. You raise your stake after a loss instead of a win, which is really just the Martingale pattern: chasing losses with bigger and bigger bets. Losing runs get expensive fast, and table limits can end the progression before a win arrives. A few guides cap it at three doublings, and our Martingale guide covers the risks in more detail.
Extended Paroli (four-win cap)
Extended Paroli raises the cap from three wins to four. With a €5 unit, the stakes run €5, €10, €20 and €40, and a full streak pays €75 instead of €35. Four wins in a row happens about half as often as three, at roughly 5.6% on a European wheel and 5.0% on an American one, compared with 11.5% and 10.6% for three. Each extra win also means one loss takes back more profit. Some guides use the word "extended" for the standard version, but here it means a longer cap.
Reverse Martingale
Reverse Martingale, also called Anti-Martingale, is the same idea as Paroli but without the cap: you double after each win and return to 1 unit after a loss. With no stopping point, the stake keeps growing for as long as the streak lasts, and the loss that ends it hands back all the profit.
Pros and Cons of the Paroli Strategy
Paroli's main strengths are low stakes and simple rules. Its main weakness is that it can't touch the house edge.
Pros
Unlike Martingale, Paroli doesn't need a large bankroll. The three-win cap keeps bet sizes down, whereas Martingale needs a big bankroll to keep doubling through a losing streak.
Low stakes also make it less risky than strategies that raise your stake after a loss. A doubling system with no cut-off on winning bets could see a huge upset after a winning streak. That's why Paroli stops the doubling after three wins and resets the stake instead of letting a streak run.
The system is also relatively simple. No maths is involved, and the logic is clear after every win or loss. That leaves newer players free to focus on the game itself, while experienced players have a clear staking plan.
Cons
Even-money bets sound like a coin flip, but they aren't. Your chance of winning a spin is 47.37% on an American wheel and 48.65% on a European one, because the green zero (or zeros) counts as a loss.
Only one of the eight runs delivers the big +7, and the house edge makes it rarer still, so the odds of coming out ahead are stacked against you.
The three-win cap is also easy to ignore. When a streak is going well, it's tempting to keep going, and one loss at that point wipes out all the profit from the cycle.
Does the Paroli Betting System Work?
Unfortunately, no betting system can guarantee success. Paroli has certainly been around a long time, but it can't claim a lasting success rate in roulette or any other casino game. Randomness and the house edge mean any betting system will eventually fail with enough time, even for expert gamblers.
There's nothing wrong with trying a betting strategy. Just keep in mind that none of them guarantees a win, and the same goes for betting without a system. A plan gives you structure: a clear idea of what each bet costs and when to stop. It won't change the house edge, as the odds table above shows.
Paroli Betting System Tips
If you're going to try Paroli, keep these tips in mind. Most of them apply to other strategies too:
- Try it in demo mode first. Virtual roulette tables at online casinos have a demo mode you can choose when you enter the game. It lets you play with fake funds at your own pace, so you can see how the stake pattern plays out and whether it suits your style without risking real money.
- Only bet at licensed casinos. That goes for any game. Stick to online casinos you trust that are regulated by a gambling authority. UK players should look for a UK Gambling Commission (UKGC) licence, which you can check on the Commission's public register. Players elsewhere should check that the operator is licensed to serve their country.
- Find out how the casino looks after your money. A licence means games and player protection must meet certain standards, though how operators keep customer funds safe differs from one to the next, so it's worth reading that part of their terms.
- Look at the table rules before you play. La Partage brings the house edge on even-money bets down to about 1.35%, as the odds table shows, and En Prison (where the bet is held for another spin) is commonly cited as doing the same. Not every casino has these tables.
- Be mindful of your bankroll. Work out what 1 betting unit will be before you start. It should be a small percentage of your overall gambling bankroll, preferably around 1% to 5%. Even 5% may be a bit high, since just 20 losses in a row would wipe out your bankroll.
- Remember the three-win cap. Feeling the rush of a winning streak may tempt some to ignore the cap. After all, if you are on a streak, why not see where it goes? It can lead to a big upset when you sink all of your previous winnings into a losing bet. The cap is there for a reason, so stick to it.
- Set your limits before you start. Most licensed casinos let you set deposit and loss limits and use reality checks, so it's worth switching them on. You must be of legal gambling age, which is 18 in the UK.
- If gambling stops being fun, get support. GamStop offers free self-exclusion from UK-licensed sites, and BeGambleAware and GamCare can point you to free, confidential support. Outside the UK, look for your own country's self-exclusion scheme and helpline.
Is the Paroli System Worth Trying?
Worth trying in demo mode, yes, if you like having a clear plan for your stakes. Like any betting strategy, though, Paroli has its flaws and doesn't guarantee a win at the casino, because no pattern of bets changes the house edge. The most important thing about any casino game is having fun. If you play for real, keep your unit small, stick to the three-win cap, and let your limits decide when to stop.
Paroli System FAQ
Is the Paroli System a Good Strategy for Roulette?
Paroli won't beat roulette, as the house edge stays the same no matter how you place your bets. It gives you clear rules and small bets while you're losing, so some players like it for adding structure to a session.
What is the Difference Between Paroli and Martingale?
Martingale doubles your stake after a loss, and Paroli doubles it after a win. With Martingale, five losses in a row leave you facing a 32-unit bet, while Paroli risks only 1 unit per cycle.
Is Paroli the Same as Reverse Martingale?
Almost. Paroli is a reverse Martingale with a cap of three wins, so you bank the profit instead of letting the stake keep growing. The Paroli variants section above has the details.
How Many Wins Should You Stop at With Paroli?
Most guides stop at three wins, and that's what we use here. Extended Paroli stops at four, which pays €75 instead of €35 with a €5 unit, but happens about half as often. Whatever cap you pick, decide on it before you start.
Does Paroli Work Better on European or American Roulette?
The rules are the same, but a European wheel is the better choice: the house edge is 2.70% against 5.26%, and three wins in a row land more often (about 11.5% of the time against 10.6%). French tables with La Partage cut the house edge further, to about 1.35%.
What Bankroll Do I Need for the Paroli System?
A losing cycle costs 1 unit, so a 40-unit bankroll covers 40 losing cycles in a row. With a €5 unit, that's €200. Only stake money you can afford to lose.
Can You Use the Paroli System in Blackjack or Baccarat?
It can be used in both, provided the bet pays 1:1. In blackjack, that covers ordinary winning hands, and in baccarat it covers the player bet. You'll also need to decide what to do about ties and pushes; repeating the same stake is the simplest option. The casino keeps its edge in every game, so the system doesn't change the maths.