Bonus Bet (Free Bet)

A bonus bet — also called a free bet — is a voucher a sportsbook issues you instead of cash. You can attach it to a wager just like real money, but it behaves differently when the bet settles. Win, and the book pays you the profit in withdrawable cash; the bonus bet itself evaporates. Lose, and you simply lose the voucher — no real money was ever at risk. That one distinction, “stake not returned,” is the entire mechanism, and it’s also the single most misunderstood detail among new bettors.

Books hand these out for all sorts of reasons: a new-customer signup offer, a “bet $5, get $150 in bonus bets” promo, a refund on a losing first bet, or a loyalty reward for high-volume players. The dollar amount printed on the voucher always overstates its real value, because a $100 bonus bet is not worth $100 to you — it’s worth whatever profit it can generate, minus the stake you’ll never see again.

The math that matters here is expected value, and it changes depending on the odds you use it on. On a pick’em-style number like -110, a $100 bonus bet returns roughly $90.91 in cash if it wins and $0 if it loses — so its expected value at true 50/50 odds is around $45. That’s why sharp bonus-bet users hunt for plus-money underdogs instead of chalk favorites: the same $100 voucher staked on a live dog at +300 either nets you $300 in cash on a win or costs you nothing on a loss, which is a dramatically better risk-free payoff profile than parking it on a heavy favorite where the potential win is small relative to the stake you’re forfeiting either way.

Example

Say DraftKings credits your account with a $75 bonus bet after your first cash wager settled as a loss. You decide to put it on the Detroit Lions moneyline at +145 to beat the Green Bay Packers on a Sunday afternoon.

• You place the full $75 bonus bet on Lions +145. No cash leaves your balance — the site debits the voucher instead.
• The Lions win. At +145, a $75 stake would normally return $75 + ($75 × 1.45) = $75 + $108.75 = $183.75 total.
• Because it’s a bonus bet, the $75 stake portion is stripped out at settlement. You’re credited only the $108.75 in winnings, deposited as cash (or, at some books, as bonus funds with a one-time playthrough requirement — check the terms).
• Net result: you turned a $75 voucher into $108.75 in real cash off a game where you had zero dollars actually exposed.

Compare that to using the same $75 on a -160 favorite instead. A win nets you $75 × (100/160) = $46.88 — real money, but a much smaller haul from the same voucher. The underdog play converted more of the bonus bet’s face value into actual cash, which is the whole optimization exercise in one comparison.

Key Points

• Stake is never returned, win or lose: Budget the voucher’s real value as “potential winnings only,” not its face amount — a $75 bonus bet on -110 is worth roughly $34 in expected cash, not $75.
• Plus-money dogs convert more value than favorites: Because you never get the stake back, betting a bonus voucher on -300 chalk wastes most of its potential; a live underdog at +150 or better extracts far more cash per dollar of bonus.
• Read the settlement type before you count the winnings: Some books pay bonus-bet profit as instant withdrawable cash, others as bonus funds requiring a 1x rollover — that difference changes how fast you can actually pocket the money.
• Bonus bets usually expire, often within 7 to 30 days: An unused voucher is worth exactly zero, so don’t let a promo sit while you wait for the “perfect” spot — a decent +200 line today beats a theoretical +400 line you never place before expiration.
• Splitting a large bonus bet can smooth variance: Turning one $200 voucher into four $50 bets across different games raises your odds of cashing at least one, though it slightly lowers the ceiling on any single payout — decide based on whether you want a shot at a big hit or a more reliable partial return.
• Middling or hedging can lock in near-guaranteed profit: Pairing a bonus bet on one side of a game with a small cash wager on the other side, sized correctly, can convert the voucher into cash regardless of outcome — the tradeoff is giving up some of the upside a straight underdog bet would offer.