What a Free Bet Is Actually Worth
A $100 free bet is never worth $100. How much of it you actually keep depends on the odds you use it at — and the answer runs the opposite way to almost everyone’s instinct.
9 min read
The short answer
- Most free bets are “stake not returned”: you keep the profit, not the stake.
- That makes the value 1 − (1 ÷ decimal odds) of face value, before any margin.
- At +100 a $100 free bet is worth about $50. At +400 it is worth about $80.
- Longer odds convert better — the opposite of the instinct to “use it on something safe”.
- Hedging a $100 bonus bet at +200 against −180 locks in $71.43 in cash, guaranteed.
- An odds boost is only valuable if the underlying price was not already padded to absorb it.
Stake not returned: the detail that changes everything
A normal bet returns your stake plus your profit. A free bet — also called a bonus bet — almost always returns only the profit. The token is consumed whether you win or lose.
So a $100 free bet at +100 does not return $200. It returns $100. That single detail is where most of the value goes.
profit if it wins = amount × (decimal − 1) expected value = p × amount × (decimal − 1) At fair odds, p = 1 / decimal, so conversion rate = 1 − (1 / decimal)
At fair odds. The p here is the true probability, so any real market’s margin makes the number slightly worse.
Why longer odds convert better
Here is the counter-intuitive part. Because you lose the stake either way, what you are buying is profit-per-token — and long odds produce far more profit per token.
| Odds used | Profit if it wins | Value of a $100 free bet | Conversion |
|---|---|---|---|
| −110 | $90.91 | $47.62 | 47.6% |
| +100 | $100.00 | $50.00 | 50.0% |
| +200 | $200.00 | $66.67 | 66.7% |
| +400 | $400.00 | $80.00 | 80.0% |
| +800 | $800.00 | $88.89 | 88.9% |
The instinct is to use a free bet on something safe, so it does not go to waste. That instinct is backwards. A free bet on a heavy favourite at −110 keeps under half its face value; the same token on a +400 underdog keeps four fifths of it.
The trade is variance: at +400 the token expires worthless four times in five. You are choosing a higher average with a much lower hit rate — which is fine for a token you did not pay for, and a genuinely bad idea with real money at the same odds unless the price is also +EV. The free bet calculator runs it for any price.
Turning a bonus bet into guaranteed cash
If you would rather not gamble the token at all, you can hedge it. Place the free bet at long odds, then back the other side with real money at another book, sized so both outcomes pay the same.
hedge stake = bonus × (bonus decimal − 1) / hedge decimal $100 bonus at +200 (3.00), hedge at −180 (1.5556) hedge stake = 100 × 2.00 / 1.5556 = $128.57 if the bonus wins: $200.00 − $128.57 = $71.43 if the hedge wins: $128.57 × 0.5556 = $71.43 guaranteed: $71.43 — a 71.4% conversion
The hedge divides by the hedge price rather than multiplying by the bonus price, because the bonus stake does not come back.
Seventy-one percent of face value, in cash, with no outcome risk — better than the 66.7% expected value of simply firing the token at +200 and better than any safe-favourite use of it. The bonus bet conversion calculator sizes the hedge for any pair of prices.
Odds boosts and profit boosts
A boost raises the profit portion of a price by a stated percentage. It applies to the profit, not the total return, so the effect is smaller than it sounds — and the direction of the gain is easy to check.
boosted decimal = 1 + (decimal − 1) × (1 + boost)
| Original | Boost | Boosted price | Implied probability |
|---|---|---|---|
| +100 | 50% | +150 | 50.00% → 40.00% |
| +200 | 25% | +250 | 33.33% → 28.57% |
| −110 | 30% | +118 | 52.38% → 45.83% |
A boost is genuinely valuable when it takes a fairly-priced market to a price better than fair. It is worth nothing when the underlying price was padded first — a market offered at −140 where every other book has −110, then boosted 30%, has given you nothing. Always check the unboosted price against another book before treating a boost as value. The odds boost calculator converts the boost into a real price you can compare.
What promos are and are not
Promotions are customer acquisition. They are priced by people who know exactly what the average customer does with them, and the average customer uses a free bet on a favourite and keeps under half its value.
Extracting closer to the full amount is legitimate and entirely mechanical — long odds or a hedge, terms permitting. It is also a one-off per promotion rather than a strategy, and operators do restrict accounts that only ever appear for a bonus.
What it is not is a source of ongoing edge. Once the sign-up offers are used, you are betting into the same margins as everyone else, and taking the best price matters considerably more over a season than any promotion did.
Common questions
- What is a $100 free bet actually worth?
- Between about $48 and $89, depending on the odds you use it at. Because most free bets return only the profit and not the stake, the value is roughly 1 − (1 ÷ decimal odds) of face value: about $50 at +100, about $80 at +400.
- Should I use a free bet on a favourite or an underdog?
- An underdog, if the terms allow. Since the stake is not returned either way, what matters is profit per token — a $100 free bet keeps 47.6% of its value at −110 and 80% at +400. The trade is that it expires worthless far more often.
- How do I convert a bonus bet into cash?
- Place it at long odds and hedge the other side with real money at another book. A $100 bonus at +200 hedged against −180 needs a $128.57 hedge and locks in $71.43 whichever way it lands — a 71.4% conversion. Check the promotion terms first; some forbid it.
- Are odds boosts worth using?
- Only if the price underneath the boost was competitive to begin with. A market padded to −140 and then boosted 30% may still be worse than the −110 available elsewhere. Compare the unboosted price to another book before calling a boost value.
- Why do sportsbooks give away free bets?
- Customer acquisition, priced by people who know what the average customer does with them — which is use them on a favourite and keep under half the face value. Extracting more is legitimate, mechanical, and generally a one-off per promotion.