Several chemicals and chemical combinations were evaluated for terminating late-season fruiting of cotton. Termination of late-season fruiting was sought to remove the food supply of the pink bollworm [Pectinophora gossypiella (Saunders)] and, thereby to interrupt its life cycle by preventing the accumulation of diapausing (overwintering) larvae. The chemicals were applied in foliar sprays on 1, 2, and 3 September. Chlorflurenol at 0.56 kg/ha, alone or in combination with ethephon at four concentrations from 0.14 to 1.12 kg/ha or thidiazuron at three concentrations from 0.0056 to 0.056 kg/ha and a combination of thidiazuron at 0.022 kg/ha plus ethephon at 0.56 kg/ha, drastically reduced late-season fruiting without causing problems with harvest. The combination of chlorflurenol plus ethephon was the most effective in reducing the numbers of green bolls present on plants on 13 to 15 October. Pink bollworm larvae diapaused in significant numbers from bolls samples on 22 September, or later. Average lint yield on 26 to 26 October was estimated at 1230 kg/ha (2.2 ba/acre) and was unaffected by treatment. Yield would have been significantly higher on the treatments that did not terminate fruiting if the green bolls had been permitted to open. Cultural practices are needed to increase yields from the first fruiting cycle or to incorporate earliness into two fruiting cycles.