Timing nitrogen applications to the biological needs of a crop is an effective way to reduce nitrogen losses to the environment. However, this strategy may carry a production risk and conflict with farmers' economic objectives. A field-level production decision model was used to estimate on-farm costs associated with timing nitrogen applications for crop needs in Indiana. For risk-neutral farmer, the estimated cost is less than $1 per acre with a reduction of 11 pounds of residual nitrogen. For a risk-aversion farmer, the estimated cost is up to $37 per acre with a reduction of 96 pounds of residual nitrogen.