Bonus Bet Calculator

Work out the exchange lay that converts a stake-not-returned bonus bet into a guaranteed retained value.

Odds format: Decimal Fractional American

Bet details

Bonus amount $

Back odds

Lay odds

Commission

Lay %

You should lay

Liability

Retained value

Guaranteed

% of bonus

If back wins

Bookie pays

Betfair

If back loses

Betfair

What this calculates

A stake-not-returned (SNR) bonus bet pays only the winnings if it lands, and nothing if it loses. Backing the bonus at a bookmaker and laying the same selection on an exchange converts that all-or-nothing bet into the same retained value either way. The calculator assumes the bonus stake is not returned.