Betting maths and calculators
Can a bookmaker lose money despite offering negative-EV odds?
Direct answer
Yes. Individual outcomes and short-term results can favour customers; a theoretical margin is not a guarantee on every event.
How to use this answer
This answer is based on the mathematical principle or published rule identified in the source below. If the question involves a live betting market, confirm its settlement definition before applying it to a specific bet.
Use the precise stake, decimal odds, market terms and outcome probabilities when calculating the result. Expected value measures an average over hypothetical repetitions, not a guaranteed profit.