What each bet does to your risk and to the margin you pay, with the arithmetic that most betslips hide.
One selection, one price, one result. Stake 100 at 2.50: win and receive 250, lose and lose 100. The margin is paid once, and it is the bet every professional uses almost exclusively. If a bookmaker offers a promotion that requires accumulators, that is the reason.
Two or more selections combined; every one must win. The odds multiply: 1.80 x 1.80 x 1.80 x 1.80 = 10.50. So do the margins. If each leg carries a 5 percent margin, the fair price of the four-leg bet is about 12.5, and you are receiving 10.50: an effective margin of almost 19 percent. Accumulators are where bookmakers make their best money, which is why they are promoted with insurance, boosts and "acca club" rewards.
Combinations that pay even if a selection loses, by placing several smaller bets at once. A Trixie takes three selections and places four bets: three doubles and a treble. A Yankee takes four selections and places eleven: six doubles, four trebles, one fourfold. A Lucky 15 adds the four singles for fifteen bets. A "2 out of 4" system places the six doubles only. The stake is per bet, so a Yankee at 10 costs 110. Two winners in a Yankee return one double; three winners return three doubles and a treble. Systems soften the all-or-nothing of an accumulator, but every bet inside them still carries the margin.
Two bets in one: a win bet and a place bet, at a fraction of the win odds for a set number of places. A horse at 10.00 each-way at a quarter of the odds for three places: stake 10 each-way costs 20; if it finishes second, the place part pays at (10 - 1) / 4 + 1 = 3.25, returning 32.50; if it wins, both parts pay, 100 + 32.50. Standard in racing and golf; the place terms are where operators compete.
Double chance covers two of three outcomes (home or draw, for example) at a short price. Draw no bet refunds the stake on a draw; it is the Asian handicap at zero, and usually priced better under that name.
Several markets from one match combined: a team to win, over 2.5 goals, a player to score. The outcomes are correlated, and the operator prices the correlation with an extra margin that we measured at 15 to 25 percent on typical three-leg builders. Entertaining, expensive.
Handicaps give one side a head start so the odds even out; see our Asian handicap guide. Totals bet on the number of goals or points; see over/under. Outrights bet on a season or tournament winner, at a margin that is high because the money is locked up for months.
Singles, on main markets, at the best available price.
It pays out more often, for a much larger total stake; the margin per bet is unchanged.
Four selections, fifteen bets: four singles, six doubles, four trebles, one fourfold.