The general rule regarding parlays is: DON'T.
Parlays generally carry an increased house edge than straight bets, therefore you give the book a more impressive advantage over you when you play them. That, alone, is reason enough to suppress the misplaced feelings of greed coupled with fear that often result in betting parlays. People think they are risking less with parlays, however they are not. They believe they can win more with parlays, but they cannot. The higher win with parlays is far outweighed by the bigger probability of losing. Parlay bettors are actually risking more, with less possibility of collecting.
A parlay is not an individual bet. It really is two bets -- a one-unit bet on 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 no matter which team gets the double bet. When one team wins and one team loses, however, the double bet is presumed to have been on the loser. How smart is that for the bettor? Just do it, create a parlay. We'll wait until both games are over, and in case of a split we'll put the double bet on the loser. If your bookmaker sold you a parlay with that line, just how many of you'll still make the bet?
A parlay is also bad money management. In a parlay you either bet double on the next team, or nothing on that same team, depending upon if the first game won or lost. That adds an element of luck to your betting that doesn't must be there. The skilled handicapper is always seeking to make smart investments. He tries to get rid of the result of luck to the greatest extent possible in order to make his results as predictable as you possibly can.
As with every rule, however, there are exceptions. The exception to the rule regarding parlays occurs when 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 player to consistently parlay the initial half with the game. The ball player parlayed totals by combining the over in the initial half with the over in the game, and the under in the first half with under in the overall game. Both parlays were made in the same game. Every time the player won he would win 2.6 times his bet. Betting K8CC on each parlay, if one of them won, the 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 would lose $200.
At first glance, this were a great chance for the book. The normal coin-flip odds of winning one parlay from the two are 50-50. As far as the bookie was concerned the bettor ought to be winning $160 half enough 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 both halves of every parlay were co-dependent. By the end of the initial half, the bettor was hardly ever in a 50-50 situation.
Take the Thursday night game between Utah and Air Force. The overall game total was 53 and the initial half total was 27. At the end of the first half, the score was 31-21, for a complete of 52 first-half points. The initial half of one of the parlays, the "over" in the initial half was successful. For the parlay probability to be correct, there should now be considered a 50-50 probability of winning the "over" for the game. Obviously the odds of winning the "over" in the game weren't 50-50 but better than 99% and only the "over." The player only needed to win the first 1 / 2 of the parlay to be virtually assured that he would collect 2.6 times his money instead of just $10 for $11.
Before you rush out to use this, be aware that most off-shore books are far too smart to let you parlay first half to game. Should they do let you do this, start worrying about collecting because that book will be taken to the cleaners.
There are, however, some less obvious co-dependent parlays that may still be made at many books. One kind of co-dependent parlay is the parlay of the side and total in exactly the same game.
Any game where the total is less than double the spread can provide you an edge in parlaying side to total in the same game. We've already discussed, in a prior article, how to use these anomalous side and total combinations to hedge one another and increase your win with very little increase in risk. This type of bet, however, required that you have an impression on the side or the full total. Parlaying is another method to increase your potential win on these games, or even to develop a potential win in case you have no opinion.
You can find two games this Saturday that qualify. They are 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 believe that Virginia covers the 25 points, they must hold Duke to no more than 11 points or the game will go over the total. The much more likely it becomes during the game that Virginia will cover 25 points, the more likely it becomes that the game will review 48 �. The wider Virginia's winning margin, the much more likely the game will go over. If you want Virginia to cover the spread, and you 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 standard 25%. Likewise, if the scoring stays low, it is less likely that Virginia will cover the 25 points. Subsequently, the probability a parlay of the under with the underdog will win is higher than the normal 25%.
Assuming you have no opinion on the game, you can parlay the favorite with the "over" and the underdog with the "under" and collect sufficiently often to exceed the losses when both parlays lose. In the only real other game meeting the qualifications this week -- Friday's game between California -30 against New Mexico State with a total of 58 -- the under has already won with the underdog for an absolute two-parlay spread.
The closer the posted total is to the spread privately, the better win-rate will undoubtedly 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 wouldn't normally allow such bets), but there is a sufficient co-dependency in the games with low totals and high spreads to help make the strategy profitable long-term.
Not all bookmakers will help you to parlay the side to the full total in exactly the same game, because increasingly more are realizing that these bets are occasionally co-dependent. But, enough books still do allow such bets that you consider including such bets in your professional betting arsenal.
If your bookmaker provides "if/reverse" bets, you can replace the parlay bet having an "if/reverse" bet and achieve greater success.