What is Arbitrage Betting?

Arbitrage betting (also called "arbing" or "sure betting") means placing bets on every possible outcome of a game — across different sportsbooks — so that you profit no matter who wins.

It sounds like magic, but it's just math. It works because different sportsbooks set their own odds independently, and sometimes they disagree enough to create a gap you can profit from.

Let's say it's Chiefs vs. Bills. Here's what two books are offering:

Both books agree the Chiefs are favoured — they disagree about by how much. DraftKings has the Chiefs at −130, a shorter price than FanDuel's −155, which leaves FanDuel paying +140 on the Bills. Take the best price on each side and you have backed both teams at better than the true odds.

−130 implies a 56.5% chance. +140 implies a 41.7% chance. Together that is only 98.2% — the two prices leave 1.8% of probability unaccounted for, and that gap is your profit. Neither book is mispriced on its own: DraftKings's two-sided market holds 3.0% and FanDuel's holds 2.5%. The edge exists only because you are shopping across both.

Note what the net subtracts: the whole $1,000 you put at risk, not just the losing leg. Both stakes leave your pocket, so a return that beats one stake but not the total is a loss dressed up as a win — the most common way a hand-worked arb goes wrong.

Either way, you profit — at least +$17.60 on a $1,000outlay. That's arbitrage.

Sportsbooks employ teams of people and algorithms to set odds. They're good at it — but they're not perfectly synchronized. Odds change constantly based on betting volume, news, injuries, and other factors.

When they move independently, gaps open. These gaps are usually small (1-3%) and close quickly as bettors exploit them — always confirm the odds are still live at each book before placing both legs.

Yes, completely legal — as long as sports betting itself is legal in your state. You're simply placing bets at multiple sportsbooks, which any bettor can do.

Sportsbooks don't love it (they lose money), and they may eventually limit your account if you only arb. But for the purposes of clearing signup bonuses and taking advantage of promos, it's a normal and accepted practice.

• Odds change before you finish. You need to place both bets quickly. If odds move between bets, the arb might disappear.
• Human error. Entering the wrong amount can turn a profit into a loss. Double-check everything.
• Account limits. If you arb frequently, some books may reduce your max bet size.