The general rule regarding parlays is: DON'T.
Parlays generally carry a higher house edge than straight bets, therefore you give the book a more impressive advantage over you once you play them. That, by itself, is reason enough to suppress the misplaced feelings of greed combined with fear that often lead to betting parlays. People think they are risking less with parlays, but they are not. They believe they can win more with parlays, however they cannot. The higher win with parlays is far outweighed by the higher possibility of losing. Parlay bettors are actually risking more, with less possibility of collecting.
A parlay is not an individual bet. It is two bets -- a one-unit bet using one team and a two-unit bet on the other. Which team gets the two-unit bet? In point-spread betting at constant money odds, if both teams win or both teams lose it doesn't matter which team gets the double bet. When one team wins and something team loses, however, the double bet is presumed to possess been on the loser. How smart is that for the bettor? Go ahead, create a parlay. We'll wait until both games are over, and in case there is a split we'll put the double bet on the loser. If your bookmaker sold you a parlay with that line, how many of you'll still make the bet?
A parlay can be bad money management. In a parlay you either bet double on the second team, or nothing on that same team, depending upon if the first game won or lost. That adds some luck to your betting it doesn't ought to be there. The skilled handicapper is always wanting to make smart investments. He tries to get rid of the effect of luck to the best extent possible to make his results as predictable as you possibly can.
Much like every rule, however, you can find exceptions. The exception to the rule regarding parlays occurs once the two bets are co-dependent.
I knew one bookmaker who was taken for tens of thousands because he didn't understand the co-dependency of certain bets. He allowed a new player to consistently parlay the first half with the game. The ball player parlayed totals by combining the over in the first half with the over in the overall game, and the under in the initial half with under in the game. Both parlays were made in the same game. Every time the player won he would win 2.6 times his bet. Betting $100 on each parlay, if one of these won, the ball player would win $260 and lose $100 on another parlay for a net win of $160. He could never win both parlays. If he lost both parlays he'd lose $200.
Initially, this appeared to be a great chance for the book. The normal coin-flip odds of winning one parlay out from the two are 50-50. So far as the bookie was concerned the bettor should be winning $160 half the time, and losing $200 half enough time. The bettor, however, making $500 parlays, was ahead a lot more than $20,000 after six months, and the book started to look at what the bettor was doing more carefully.
The problem for the bookmaker was that the two halves of every parlay were co-dependent. At the end of the first half, the bettor was hardly ever in a 50-50 situation.
Take the Thursday night game between Utah and Air Force. The game total was 53 and the initial half total was 27. At the end of the initial half, the score was 31-21, for a total of 52 first-half points. The first half of among the parlays, the "over" in the initial half was a winner. For the parlay probability to be correct, there should now be a 50-50 possibility of winning the "over" for the overall game. Obviously the odds of winning the "over" in the overall game weren't 50-50 but much better than 99% in favor of the "over." The player only had a need to win the first half of the parlay to be virtually assured he would collect 2.6 times his money instead of just $10 for $11.
Before you rush out to try this, remember that most off-shore books are much too smart to enable you to parlay first half to game. Should they do let you do this, start fretting about collecting because that book will be taken to the cleaners.
You can find, however, some less obvious co-dependent parlays that may still be made at many books. One kind of co-dependent parlay may be the parlay of the side and total in the same game.
Any game where the total is less than double the spread can provide you an advantage in parlaying side to total in exactly the same game. We've already discussed, in a prior article, how exactly to use these anomalous side and total combinations to hedge each other and boost your win with hardly any increase in risk. Such a bet, however, required that you have an opinion on the side or the full total. Parlaying is another method to boost your potential win on these games, or to develop a potential win should you have no opinion.
There are two games this Saturday that qualify. They're Virigina -25 over Duke with a complete of 48 �, and Kansas St. -24 � vs. North Texas with a complete 46 �).
In the Virginia game, if you were to think that Virginia covers the 25 points, they must hold Duke to no more than 11 points or the overall game will go over the total. The more likely it becomes through the game that Virginia covers 25 points, the much more likely it becomes that the overall game will go over 48 �. The wider Virginia's winning margin, the more likely the game will review. If you like Virginia to cover the spread, and you also believe that Duke will never be shut out, in that case your probability of winning a parlay on Virginia and the over are higher than the normal 25%. Likewise, if the scoring stays low, it is not as likely that Virginia will cover the 25 points. Due to this fact, the probability that a parlay of the under with the underdog will win is higher than the normal 25%.
Should you have no opinion on the overall game, you can parlay the favourite with the "over" and the underdog with the "under" and collect sufficiently often to exceed the losses when both parlays lose. In win55 meeting the qualifications this week -- Friday's game between California -30 against New Mexico State with a complete of 58 -- the under has recently won with the underdog for a winning two-parlay spread.
The closer the posted total is to the spread on the side, the better win-rate will be on the parlay "spread" bet. The co-dependency in side to total parlays isn't as strong as parlaying first half and game totals (if it were, most books would not allow such bets), but you will find a sufficient co-dependency in the games with low totals and high spreads to make the strategy profitable long-term.
Not all bookmakers will allow you to parlay the medial side to the full total in the same game, because increasingly more are realizing these bets are sometimes co-dependent. But, enough books still do allow such bets so you might consider including such bets in your professional betting arsenal.
If your bookmaker provides "if/reverse" bets, it is possible to replace the parlay bet with an "if/reverse" bet and achieve greater success.