Free Bet Conversion: How to Guarantee Profit from Sportsbook Promos
What Is Free Bet Conversion?
Free bet conversion is the process of turning a sportsbook's free bet promotion into guaranteed cash by placing the free bet on one side and hedging with real money on the other side at a different sportsbook.
Sportsbooks offer free bets as incentives: sign-up bonuses, reload offers, loyalty rewards. Most casual bettors use them randomly and accept whatever outcome they get. Smart bettors convert them into guaranteed profit every time.
How Free Bets Work
A free bet lets you place a wager without risking your own money. If it wins, you receive the profit only (not the stake). If it loses, you lose nothing.
This "profit only" structure is key. A $100 free bet at +200 (decimal 3.00) returns $200 profit if it wins, not $300. The sportsbook keeps the free bet stake regardless.
Because of this, a free bet is worth less than its face value. A $100 free bet is typically worth $60-80 in guaranteed cash when properly converted.
The Conversion Strategy
The strategy is simple: use the free bet on a heavy underdog (high odds) at one sportsbook, and hedge with a real money bet on the opposite side at another sportsbook.
Why Underdogs?
Because free bets only return profit (not stake), higher odds maximize the profit portion relative to the stake. At +100 (decimal 2.00), a $100 free bet only returns $100 profit. At +400 (decimal 5.00), it returns $400 profit.
The higher the odds on your free bet side, the higher your conversion rate.
Step-by-Step: Converting a Free Bet
Step 1: Find an Event with High Odds
Look for a market where one side has high odds (ideally +300 to +600 or higher). Moneylines with clear underdogs work well.
Step 2: Place the Free Bet on the Underdog
Use your free bet on the high-odds side. For example, $100 free bet at +400 (decimal 5.00).
Step 3: Calculate the Hedge Stake
Use this formula:
Hedge Stake = (Free Bet x (Free Bet Odds - 1)) / Hedge Odds
Where:
- Free Bet = free bet amount ($100)
- Free Bet Odds = decimal odds on the free bet side (5.00)
- Hedge Odds = decimal odds on the opposite side at another book
Step 4: Place the Hedge with Real Money
If the hedge side is at -500 (decimal 1.20):
Hedge Stake = ($100 x (5.00 - 1)) / 1.20
Hedge Stake = ($100 x 4) / 1.20
Hedge Stake = $333.33
Step 5: Collect Guaranteed Profit
| Outcome | Free Bet Result | Hedge Result | Net Profit |
|---|---|---|---|
| Underdog wins | +$400 | -$333.33 | +$66.67 |
| Favorite wins | $0 (free bet lost) | +$66.67 | +$66.67 |
Guaranteed profit: $66.67 from a $100 free bet, which is a 66.7% conversion rate.
Understanding Conversion Rates
The conversion rate is the percentage of the free bet's face value you lock in as guaranteed profit. It depends entirely on the odds available.
Conversion Rate by Odds
| Free Bet Odds | Hedge Odds (approx.) | Conversion Rate |
|---|---|---|
| +150 (2.50) | -175 (1.57) | ~50% |
| +200 (3.00) | -250 (1.40) | ~57% |
| +300 (4.00) | -400 (1.25) | ~65% |
| +400 (5.00) | -500 (1.20) | ~67% |
| +500 (6.00) | -650 (1.154) | ~70% |
| +700 (8.00) | -900 (1.111) | ~73% |
Target: 65-80% conversion rate. Anything below 60% means the odds gap between books is too wide. Use a free bet calculator to quickly evaluate opportunities.
What Affects Conversion Rate
- Odds on the free bet side. Higher odds = higher conversion. +400 or above is ideal.
- Odds spread between books. Tighter spread = better conversion. This is why having accounts at multiple sportsbooks matters.
- Market liquidity. Major sports and popular markets have tighter lines, leading to better conversions.
Maximizing Your Conversions
Use Multiple Sportsbooks
The more accounts you have, the better odds you'll find for both sides. What looks like a 60% conversion at one pair of books might be 72% at a different pair.
Time Your Conversions
Lines are tightest close to game time on major events. NFL and NBA moneylines on game day typically offer the best conversion opportunities.
Look for Arbitrage Opportunities
Sometimes the free bet side and the hedge side create an arb-like situation where your conversion rate exceeds 75%. These are rare but extremely valuable.
Stack with Other Promotions
Some books offer profit boosts alongside free bets. A boosted free bet at +500 that would normally be +400 dramatically increases your conversion rate.
Common Free Bet Types and How to Convert Each
Sign-Up Bonuses
"Bet $500, get $500 in free bets." The most common promotion. Place your qualifying bet, then convert the free bets using the strategy above.
Important: The qualifying bet is real money at risk. Some bettors hedge the qualifying bet too (reducing the conversion value but eliminating all risk), while others let it ride if the qualifying bet itself is +EV.
Bet-and-Get Offers
"Bet $50 on NFL, get a $10 free bet." These are smaller but add up. The same conversion strategy applies, just at smaller stakes.
Odds Boost Tokens
These boost the odds on a specific bet rather than giving you a free stake. The conversion approach is the same: place the boosted bet, hedge the other side. Boosted odds often push the bet into +EV territory even without hedging.
Second Chance Bets
"If your first bet loses, get a free bet back up to $1,000." These are essentially free bets that only trigger on a loss. The optimal strategy is to bet normally on the qualifying wager, and only convert if the free bet triggers.
Mistakes to Avoid
Converting at Low Odds
Using a free bet at +100 or +150 results in a terrible conversion rate (40-50%). Wait for a better opportunity rather than settling for bad odds.
Hedging at the Same Sportsbook
Many books flag opposing bets on the same event from the same account. Always use a different book for your hedge side.
Forgetting Free Bet Expiration
Free bets typically expire in 7-14 days. Don't let them lapse. Even a mediocre 55% conversion is better than 0%.
Not Accounting for the Qualifying Bet
On sign-up offers, the qualifying bet is real money. If you lose it and then convert the free bet at 65%, your total return is lower than the free bet face value. Factor both bets into your total expected return.
Key Takeaways
- Free bet conversion turns promos into guaranteed cash, typically 65-75% of face value
- Place the free bet on the underdog (high odds) and hedge the favorite at another book
- Higher odds = higher conversion rate, so target +300 or above on the free bet side
- Multiple sportsbook accounts are essential for finding the best odds pairs
- Track all promotions because even small $10 free bets add up over time
- Use a free bet converter calculator to evaluate each opportunity before placing
Put this into practice
Bet Hero scans 400+ sportsbooks in real-time to find +EV bets and arbitrage opportunities so you don't have to.
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