Cotton-corn rotation is a common practice in the mid-South but little is known about the year-to-year management of fertilizer and soil nitrogen (N) for this cropping system. A 5-yr field study was performed to determine the optimal nitrogen fertilizer rates for cotton and corn in rotation, including residual N following the respective crops at different N rates and yield levels. Experiments were conducted on Commerce silt loam and on irrigated Gigger silt loam. The treatments were cotton-corn rotations with 0, 150, 200 and 250 lb N/acre for corn and 0, 25, 50, 75, 100, and 125 lb N/acre for cotton. Residual cotton N increased corn yield only when no fertilizer N was applied to the corn and the cotton fertilizer N rate exceeded 75 lb/acre. Residual corn N increased cotton plant growth and yield when the cotton fertilizer N rate was 50 lb or less on Gigger silt loam and 75 lb/acre or less on Commerce silt loam. There was no yield response to residual corn N when the cotton fertilizer N rate exceeded 50 lb/acre on Gigger silt loam or 75 lb/acre on Commerce silt loam. The yield response of cotton to residual corn N was larger on Commerce silt loam than on Gigger silt loam. Residual corn N lowered the fertilizer N needed for optimal cotton yield by 30%. Most of the residual N from corn was not used by the following cotton crop, suggesting that residual corn N was not readily available for uptake by cotton.