Before any tactic: sports betting is -EV by default. The book builds a margin (the "vig" or "juice") into every price, so the average bettor loses over time. Every strategy below is about clawing that margin back or turning it positive — and none of it works without discipline. If you can't bet within a bankroll and walk away, no amount of maths will save you.
Value betting & positive expected value (+EV)
Value betting is the foundation. It means placing a bet only when your estimate of the true probability is higher than the probability the odds imply. Everything else — line shopping, bankroll rules — exists to protect and amplify value bets.
Worked example. A book prices an underdog at +150. That implies a 40% chance of winning (100 ÷ (150 + 100) = 40%). Suppose your own analysis says the team actually wins 50% of the time. Your expected value on a $100 bet:
(0.50 × $150) − (0.50 × $100) = $75 − $50 = +$25 expected profit per $100 bet.
That bet is +EV even though it loses half the time. Long-term profit comes from repeatedly backing +EV situations — not from any single result.
The hard part is estimating the true probability better than the market. Realistically, most casual bettors can't out-model a sharp book across the board — but you don't have to. You can find value in softer offshore markets (niche props, lower leagues), by reacting faster to news, and above all by never taking a worse price than you have to, which is where line shopping comes in.
Line shopping — the free edge
Line shopping is comparing the same bet across books and betting wherever the number is best. It is the single most reliable edge available to a recreational bettor because it carries no modelling skill and no extra risk — you're placing a bet you were going to make anyway, just at a better price.
The -105 vs -110 math. Standard juice is -110: you risk $110 to win $100. Reduced juice of -105 means you risk $105 to win $100. That $5 difference per bet seems tiny, but across 500 $100 bets in a year it's about $1,200 saved — larger than most welcome bonuses, banked purely by shopping to books that post -105.
To line shop you need multiple accounts. Offshore books make this easy: there's no state gating and no shared-account restriction. Reduced-juice books like BetOnline and Sportsbetting.ag regularly post -105, so they belong in any line-shopper's rotation. Compare the full field on our best sports betting sites guide.
Bankroll management
Bankroll management is what keeps you in the game long enough for an edge to matter. Even a genuinely +EV bettor hits losing streaks; poor staking turns those streaks into ruin.
- Fixed-unit staking (recommended for most): pick a unit of 1-3% of your total bankroll and bet that flat amount on standard plays. On a $1,000 bankroll, a 2% unit is $20. This is simple, robust, and survives variance.
- Percentage staking: always bet a set percentage of your current bankroll, so stakes shrink as you lose and grow as you win. More adaptive, but recalculating every bet is fiddly.
- Kelly criterion (advanced): stakes a fraction proportional to your edge. Full Kelly is mathematically optimal for growth but brutally volatile; most who use it bet quarter- or half-Kelly to tame the swings. Only worthwhile if you can accurately estimate your edge — and most can't, so fixed units are the safer default.
Never top up your bankroll mid-tilt to chase losses, and never stake money earmarked for rent, bills or savings. Your bankroll should be money you have fully accepted you could lose.
Arbitrage & hedging — the honest caveats
Arbitrage ("arbing") means backing every outcome of an event across different books at prices that lock in a guaranteed small profit regardless of the result. It's real: books disagree on numbers, and occasionally those disagreements are wide enough that betting both sides guarantees, say, a 2% return.
Why it isn't easy money. Arb margins are thin (often 1-3%), so you need large stakes for meaningful profit. Opportunities vanish within minutes as books adjust. And books actively limit or close accounts that arb consistently — you can't do it at scale without being detected. Treat arbitrage as a niche, effort-heavy tactic, not a reliable income.
Hedging is the practical cousin: placing a bet against your original position to lock in profit or reduce risk — for example, betting the other side of a futures ticket that's one leg from a big payout. Hedging sacrifices some upside for certainty. It's a legitimate risk-management tool, most useful on large outstanding bets, and the cash-out feature offshore books offer is essentially an automated (margin-loaded) hedge. See our live betting guide for how cash-out works.
How to read betting odds
You can't value-bet or line-shop if you can't read a price. All three common formats express the same thing — the implied probability — differently.
Converting American odds to implied probability:
- Favourite (negative): odds ÷ (odds + 100). For -150: 150 ÷ 250 = 60%.
- Underdog (positive): 100 ÷ (odds + 100). For +200: 100 ÷ 300 = 33.3%.
Once you can turn any price into a probability, you can compare it against your own estimate — and that comparison is the entire game. If your number is higher than the implied probability, you have a value bet.
Putting it together
A disciplined process looks like this: (1) form your own probability estimate for a market you understand; (2) convert the available odds to implied probability; (3) bet only when your estimate is higher — a value bet; (4) shop several books and take the best price; (5) stake a flat 1-3% unit; (6) record every bet and review honestly. Do that consistently and you give yourself the best realistic chance. Skip the discipline and no tactic will help.
Updated August 2026 · By Marcus Doyle · Fact-checked by Elena Park · 18+