Guide
How to Hedge a Free Bet or Profit Boost (With the Math)
The short answer
Here's how we'd work it out. If you hold a free bet at one sportsbook, you can place a cash bet on the other side of the same market at a different sportsbook, sized so both outcomes pay the same. The hedge size we'll use throughout this guide is:
hedge stake = free bet × (free-bet decimal odds − 1) ÷ hedge decimal oddsExample: a $100 free bet at +300, hedged at -340 elsewhere, needs a $231.82 cash hedge and locks about $68.18 whichever side wins. That is roughly 68% of the free bet's face value, not 100%.
A profit boost works the same way once you replace the odds with the boosted odds, but it only locks a profit if the boosted price is better than the other side's margin. If it is not, the hedge locks a small loss and you are better off skipping it or betting it straight.
None of this is guaranteed, and we don't want to oversell it. It only holds if both bets are accepted at those prices and neither is voided or limited. More on that below.
What a free bet actually pays
A typical free bet (also called a bonus bet) is stake not returned. If it wins you get the profit only, and if it loses you lose nothing of your own money. Sportsbook help pages describe this the same way: one sportsbook's help page, for example, says a $10 bonus bet at +100 that wins pays $10 in winnings and does not return the $10 stake.
So a $100 free bet at +300 pays $300 on a win, not $400. The terms of your specific offer decide this, so read yours before planning anything. Some credits do return the stake, and the maths changes (see "If the stake is returned" below).
The formulas
Let's start with the formulas we'll use for every example below. Convert American odds to decimal first: positive odds +X → 1 + X/100; negative odds -X → 1 + 100/X.
Let F be the free bet, dA its decimal odds, and dB the decimal odds on the other side (at another book).
| Case | Hedge stake H | Locked result |
|---|---|---|
| Free bet, stake not returned | H = F·(dA − 1) / dB | F·(dA − 1) − H (same as H·(dB − 1)) |
| Stake returned (site-credit style) | H = F·dA / dB | F·dA − H |
Profit boost on a cash stake S, boost b | boosted odds d' = 1 + (1 + b)·(dA − 1), then H = S·d' / dB | S·(d' − 1) − H |
Here's why the free-bet formula works. If the free bet wins you net F·(dA − 1) minus the hedge you lost, H. If the hedge wins you net H·(dB − 1) and lose nothing on the free bet. Setting those equal gives H = F·(dA − 1)/dB.
Two useful rules of thumb that follow from it:
- Free bet: with zero margin on the hedge price, the share you keep equals
1 − (implied probability of the free bet's odds). Real prices carry margin, so you keep less. - Cash or boosted bet: a lock exists only if the two prices' implied probabilities add up to less than 100%.
Worked example 1: $100 free bet at +300
Let's walk through it. Say you hold a $100 free bet at Book A and take the +300 side of a market. Another book offers the opposite side at -340.
dA= 1 + 300/100 = 4.00.dB= 1 + 100/340 ≈ 1.2941.H = 100 × (4.00 − 1) / 1.2941 ≈ $231.82.- If the free bet wins: +$300 at Book A, minus the $231.82 hedge that lost = +$68.18.
- If the hedge wins: the hedge pays
231.82 × (1.2941 − 1)= +$68.18 at Book B, and the free bet loses $0 of your cash = +$68.18.
You have put $231.82 of your own money on the hedge. That money is tied up until the game settles, and it is exposed to account limits, price moves and voids in the meantime.
Worked example 2: how the free-bet odds change the result
Longer free-bet odds generally convert a bigger share, because a free bet pays profit only and longer odds mean more profit per dollar of stake. The hedge prices below are illustrative numbers we chose, with a margin of roughly 2-3% built in, not quotes from any book.
| Free bet odds | Hedge odds | Hedge stake | Locked | Share of the $100 free bet | Share at zero margin |
|---|---|---|---|---|---|
| +150 | -170 | $94.44 | $55.56 | 55.56% | 60.00% |
| +300 | -340 | $231.82 | $68.18 | 68.18% | 75.00% |
| +500 | -600 | $428.57 | $71.43 | 71.43% | 83.33% |
| -110 | -110 | $47.62 | $43.29 | 43.29% | 47.62% |
Two things we'd point out. First, the real share is always below the zero-margin share, and the gap is the other book's margin. Second, longer odds mean a bigger hedge, so you need more cash on hand and more margin is paid on a larger bet. One public calculator that covers this also notes that at very long odds the extra margin can outweigh the extra winnings. Check your offer's minimum odds before you choose a price.
If the stake is returned
Some credits (site credit, for example) pay profit plus the stake on a win. Let's rerun the same $100 at +300, hedged at -340:
H = F × dA / dB = 100 × 4.00 / 1.2941 = $309.09- Locked result: $90.91
A free bet that does not return the stake locks $68.18 at the same prices, which is why it matters to check whether your credit returns the stake before you plan the hedge. A bet reset is different again: if the bet loses you are refunded as a $0 loss.
If the other book charges commission
Exchanges and some venues charge a commission c on winnings. Replace the hedge's decimal odds with dB_eff = 1 + (dB − 1)(1 − c) and use the same formulas. With a 2% commission, our $100 +300 example needs a $232.88 hedge and locks $67.12 instead of $68.18. (The 2% is an illustration, not any venue's rate.)
Worked example 3: a profit boost
Now let's look at a profit boost. A profit boost raises the profit, not the stake. A 30% boost on a +200 bet (decimal 3.00) makes the profit 1.3 times as large, so the decimal odds become d' = 1 + 1.30 × (3.00 − 1) = 3.60, which is +260.
You stake $50 of cash at the boosted +260. The other side is -230 at another book (dB ≈ 1.4348).
H = 50 × 3.60 / 1.4348 ≈ $125.45.- If the boosted bet wins:
50 × (3.60 − 1)= $130 profit, minus the $125.45 hedge = +$4.55. - If the hedge wins:
125.45 × 0.4348= $54.55 profit, minus the $50 boosted stake = +$4.55.
Without the boost, the same hedge at -230 locks -$4.55: the combined implied probabilities are 103.03% (over 100%). The boost turns it into a +$4.55 lock, a change of $9.09. In this example you have $175.45 of cash across the two bets, so the locked return on cash staked is 2.59%.
How big does the boost need to be? At these prices, a boost of 15% is exactly break-even (boosted odds of 3.30, +230, the mirror of the -230 hedge), so anything smaller locks a loss. Because the break-even depends on the hedge price, let's run the numbers for our own prices instead of copying this one.
If you do not hedge, a boosted bet is just a bet. Whether it is a good bet depends on the true chance of winning, which the boost does not tell you.
Common mistakes
Here are the slips that can quietly change the result, and how we'd avoid each one.
- Treating the free bet as cash. $100 of free bet is worth about $43 to $71 in the table above, not $100, and the exact amount depends on your prices.
- Using the wrong formula for the stake. If you use the stake-returned formula on a stake-not-returned free bet, you will over-hedge and lock less than you expect. Read the offer to see which applies.
- Hedging at the same sportsbook. Betting both sides at one book usually breaks promo terms and can get a promo voided or an account restricted. Use two different books.
- A different market or line. The hedge has to be the opposite side of the same market and the same line, or you have two unrelated bets.
- Ignoring minimum odds, expiry and eligible markets. The offer's terms can force the price, the market and the deadline.
- Placing one leg before the other is confirmed. Prices move and bets get rejected. If leg 1 is accepted and leg 2 changes, your result is no longer locked. Look at both prices again right before you place either bet.
- Rounding the hedge carelessly. Rounding to whole dollars moves the result by cents or a couple of dollars. Compute the result from the amount you actually place.
- Forgetting the cash has to sit somewhere. The hedge uses your own money until the event is graded, and books can hold winnings, delay withdrawals or limit stakes.
- Chasing a boost because it is labelled a boost. The test is whether the boosted price beats the other side's price after margin. See the break-even math above.
Recording both legs so the numbers stay honest
Once we're doing this across more than one book, the bookkeeping is the hard part: one bet pays profit only, the other is a normal cash bet, and each one sits at a different book. A tracker that knows a free bet loses $0 on a loss and pays profit only on a win keeps the books straight.
Our tracker, VigStamp, is a free spreadsheet-style bet tracker with sub-accounts. In the Add Bet form, the Promo & fee section has a Stake setting (Cash, Free bet, Site credit or Bet reset), a Profit boost field, and a Promo pair option with a hedge calculator: you enter the promo odds and the hedge odds, and it sizes the cash bet and shows the result either way. The pair has to be on two different books. Matching slips can link on their own when the game, market, line and opposite sides agree, or you can pair them from the bet's page. Each sub-account keeps its own balance under its book, so the free bet and the hedge each land where they belong.
You don't need our tracker to do the math in this guide. A spreadsheet and the formulas above are enough. Our tracker is there for when you want the result of each bet recorded in one place.
Responsible betting
We want to be straight with you: promos can make betting feel like free money, and they are not. Only bet what you can afford to lose, set limits before you start, and do not chase a promo with money you need. You have to be 21+ in most US states. If gambling is causing you or someone you know problems, call or text the National Problem Gambling Helpline at 1-800-MY-RESET (1-800-522-4700 also works). It is free, confidential and open 24/7, in the US.
FAQ
What is a hedge?
A second bet on the opposite outcome of a bet you already have, sized to fix the result whichever side wins.
How much of a free bet can I convert to cash?
Using the example prices above, roughly 43% to 71%, depending on the free bet's odds and the hedge price. Your offer and prices will differ.
Why did my winning free bet pay less than I expected?
Most free bets are stake not returned: you get the profit, not the stake.
Can I hedge at the same sportsbook?
Usually not a good idea. It commonly conflicts with promo terms. Use another book.
Is a profit boost always worth taking?
No. It only helps when the boosted price beats the other side after margin, or when you would have wanted to bet it anyway.
Sources
- Sportsbook help page: a bonus bet that wins pays winnings only and does not return the stake (PointsBet help centre, "I used a bonus bet and my bet won, why haven't I been paid in full?", https://helpcentre.pointsbet.ca/hc/en-us/articles/11372284639247-I-used-a-bonus-bet-and-my-bet-won-why-haven-t-I-been-paid-in-full).
- Stake-returned vs stake-not-returned formula comparison (Betting Maths, https://www.bettingmaths.co.uk/guides/stake-returned-vs-stake-not-returned/).
- Bonus bet hedge formula and the margin-versus-odds note (HedgeMath, https://hedgemath.com/calculators/bonus-bet-hedge).
- Hedge sizing and the combined-implied-probability test (TheSpread, https://www.thespread.com/betting-tools/hedge-calculator/).
- Profit-boost mechanics (profit, not stake, is boosted) (Steezanomics, https://steezanomics.com/learn/how-to-calculate-profit-boost-ev/).
- Helpline details: National Council on Problem Gambling, About the National Problem Gambling Helpline (https://www.ncpgambling.org/help-treatment/about-the-national-problem-gambling-helpline/) and the 1-800-MY-RESET announcement of January 29, 2026 (https://www.ncpgambling.org/news/1-800-my-reset-announcement/), which says existing access points including 1-800-522-4700 remain active.
All numbers in this guide were recomputed from the formulas above; the prices are illustrative, not quotes from any sportsbook.