Overlay (Gambling)

Meaning and Definition of Overlay in Gambling

The term overlay designates a condition in which the mathematical expectation or prize pool valuation provides a statistical advantage to the participant over the gaming operator. In fixed-odds wagering, an overlay occurs when the offered price exceeds the underlying probability of the outcome, resulting in positive expected value. Within the context of tournament poker, the term specifically identifies a shortfall where the total contributions from participant buy-ins fail to meet the operator’s guaranteed prize pool, necessitating a supplemental capital injection by the house to fulfill its contractual payout obligations. Under standard gaming compliance frameworks, such conditions represent a shift in the house edge, where the effective return to player (RTP) exceeds the baseline parity.