Prize draws, frequently used as an incentive in Web surveys, out-perform prepaid and promised monetary incentives (Bosnjak & Tuten, 2003). Tuten, Galesic, and Bosnjak (2004) illustrated the presence of an immediacy effect with prize draws in Web surveys. Willingness to participate and complete response were significantly higher when participants were told that the prize draw outcomes would be announced immediately upon submission of the survey than when participants were told that prize draw winners would be announced in a few weeks. The current study seeks to build upon that earlier work by examining the optimization between prize value and immediacy or delayed gratification. According to the standard discounted utility model, the utility of future events is discounted by a constant rate, which motivates people to prefer immediate over delayed rewards. A modification of this model is hyperbolic discounting model, which accommodates the empirical observation that discounting rates decline over time. Applied to prize draws in Web-based surveys, the standard discounted utility model suggests that people will prefer immediate notification of prize draw winners over delayed notification until the point at which the present value of the prize draw amount in the delayed condition exceeds the present value of the prize in the immediate condition. In other words, because people tend to discount values paid in the future, immediate notification prizes can be of lesser value than those in the delayed condition while still achieving higher response and completion rates. In an experiment completed in Fall 2004, we investigated the optimal prize values in immediate and delayed conditions via a Web-based survey among members of a panel using a 3*3experimental design with three notification variations and three levels of monetary incentive. Results indicate the optimal prize values in immediate or delayed conditions to minimize nonresponse and incomplete participation.