A single bet has one selection. It wins or loses on one event only. It is the plainest way to see how odds work.
A parlay (also called an accumulator, and "paroli" in Greek betting talk) is a multiple bet. You put two or more selections on one slip. All of them must win. If one fails, you lose the whole stake.
How the payout is calculated
The odds of the legs multiply. The payout grows fast. So does the risk.
The probability drops with every leg
For all legs to win you multiply the probabilities. Even legs that win 55% of the time give a small figure once you combine them.
Single or multiple
- A single shows clearly whether your estimate was right. Each price is judged on its own.
- A multiple pays a lot for a small stake, but it loses most of the time.
- In a multiple there is no "nearly". One wrong leg means a total loss.
- If a match is postponed, most bookmakers settle that leg at odds of 1.00. Check the terms.
The same money, two ways
Take the same three events and 30 in total. In the first way you stake 10 on each as a single. In the second you put all 30 on one parlay.
The parlay pays a large amount rarely. The singles pay smaller amounts more often. Neither is a guarantee of profit, because everything depends on whether your estimates are right.