How a round robin works
You pick your teams and choose the parlay size ("by 2s," "by 3s"). The book then creates every combination of that size. Three teams "by 2s" makes three separate two-team parlays: A+B, A+C and B+C. You are funding each of those parlays with your stake, so a three-team round robin by 2s at $10 a parlay costs $30 total, not $10.
A worked example
Say you like three -110 favorites and play a $10 round robin by 2s. You place three two-leg parlays for $30 total. If all three teams win, all three parlays cash. If one team loses, you still win the one parlay that did not include it, softening the loss instead of busting the whole ticket. That trade-off, more staked for more ways to win, is the entire point.
When a round robin makes sense
Round robins fit when you have several plays you like but do not want a single leg to sink everything. They cost more than one straight parlay and the math still favors the book on each leg, so they are a bankroll and risk-management tool, not an edge by themselves. The edge still comes from the price and the read on each individual pick.
Frequently asked questions
Is a round robin better than a parlay?
It is safer, not automatically better. You win more often because one miss does not bust everything, but you stake more and the payout on a clean sweep is lower than a single big parlay.
How much does a round robin cost?
Your per-parlay stake times the number of combinations. Three picks by 2s is 3 parlays, four picks by 2s is 6 parlays, so a $10 round robin there costs $60.
Related terms
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