We investigate how self-protection from the adoption of Improved Maize Varieties (IMV) and off-farm income affects risk premiums for smallholder maize producers in Uganda. To unbundle these effects, we specify the cost of risk to explicitly capture four risk components - mean, variance, skewness and kurtosis. Using unique plot-level panel data for Uganda, we estimate and test moments of a flexible production function based on an expanded form of the Johnson SU family distribution and proceed to simulate the degree of responsiveness of risk premiums and welfare estimates to marginal changes in the share of land under IMV and off-farm income. Scenarios of joint adoption of IMV accompanied with low and high application of inorganic fertilizer, and the effect of off-farm income when there is high and low supply of farm labor are examined. Results show that the use of IMV and off-farm income substantially reduces risk premiums and the individual effect is much higher under low fertilizer application and high supply of farm labor, respectively. Thus implying that self-protection is likely to reduce the propensity for index insurance especially if its design fails to consider the reduction in downside risk.