System 31 is a popular method of playing craps, often sold for high prices through mail order. It gets few requests for refunds because its good points far outweigh its negatives.
The 31 in the name refers to 31 times the multiple of your unit bet, so if you are a $1 unit bettor, then you need just $31 to play this sytem.
Here’s how it works.
First, if you are at the $5 level, you will need $155 and if you’re a $10 bettor, you’ll need $310 (just do the math!). For this discussion, we’ll simply look at $1 units because they are easiest to explain.
The progression itself is pretty simple and for the $1 units it always adds up to 31: $1, $1, $1, $2, $2, $4, $4, $8, $8 (total $31). You might want to find a low limit table (weekday mornings are best) and try this system out using $1 units before advancing to larger investments. It’s also easier to track this way, and you can get used to it before you move up to $5 and $10 units.
One of the best things about System 31 is you can use it on the pass line or the don’t pass line, and you can even switch back and forth (to accommodate good or bad shooters) right in the middle of the progression.
The important thing to remember is that when you win a bet, you need to press your winnings to make the next bet and then call the series over and start from the beginning. So, most of the time, you will not be making nine bets, but stopping when you’ve won two in a row.
For example, if you are using $1 units and lose the first six bets in a row you will lose a total of $11 ($1 + $1 +$1 + $2 +$2 +$4). Your next bet, according to the progression, is $4. If you bet $4 and win, you now bet $8 and if you win that, you stop. So you’ve lost six bets for an $11 loss and won only two bets for a $12 gain ($8 + $4). Even though you lost six bets and won only two, you’re still ahead.
Let’s look at the same example but with $10 units. You lose another six straight bets in a row: $10, $10, $10, $20, $20 and $40, so you’re down $110. Now you bet $40 and win, so your next bet is $80. You win this bet also so you stop because you won two in a row ($40 + $80). You’ve lost six bets in a row and won only the last two, but you’re still ahead by $10 ($120 — $110).
In the unlikely event that you lose all nine bets (31 units), you call it a day. But this will rarely, if ever, happen, because you don’t have to stay on the do or don’t side. You can watch the shooter and if he gets hot, bet with him as long as he holds the dice. Then when the next shooter gets his turn, make the same judgment again. If the dice turn cold, switch to the don’t pass side. The object here is not to stay on the pass or don’t pass, it’s to make money.
Remember to stick to the system, and do not make any other bets. Do not go over the 31 unit limit. When you are ahead put your chips in the back rack and do not touch them!