Cotton pollen is thought to exist in the gut of boll weevils for at least 24 hours. Because finding whole or broken cotton pollen grains are valuable clues in determining when boll weevils were living in cotton, the retention of cotton pollen in the gut of the weevil was examined. Boll weevils were fed cotton buds, cotton flowers, and water for five days, then they were placed into cleaned cages without any food. However they were allowed to drink water freely. Weevils were examined at 0, 24, 48, 72, 96, and 120 hours after the buds and flowers were removed. One hundred weevils were dissected at each time interval, and each gut was placed onto a glass slide. Light microscopy was used to determine the presence or absence of cotton pollen. More weevils (63%) at 0 hours contained pollen than weevils at any other interval. Whole pollen grains were not found in weevils after 24 hours. The 120 hour interval contained a single weevil with pollen. In the laboratory test, whole cotton pollen grains indicated that feeding on cotton occurred within 24 hours. When only halves and fragments of pollen were found, cotton feeding occurred 48–120 hours earlier. Additionally, when six or more cotton pollen grains were found in a weevil, it had fed on cotton within 24 hours. This information narrows the boll weevil dispersal times and distances from cotton fields and overwintering areas.