Cotton is a major fibre crop grown in South Africa; and is subjected to pest attacks, which reduce its yield and profitability for farmers. Field trials were conducted in 2017 and 2018 to evaluate three biopesticides, namely, Eco-Bb®, Bb endophyte, and Metarhizium rileyi in comparison with the insecticides Chlorpyrifos® 480 EC, Karate® EC, and Bandit® 350 SC. The objective was to determine their efficacy against sucking pests, leafhoppers Jacobiella facialis, aphids Aphis gossypii, thrips Thrips tabaci, whiteflies Bemisia tabaci, red spider mite Tetranychus urticae, and cotton stainers Dysdercus spp. Karate® significantly reduced the leafhopper population and outperformed all the other treatments. Eco-Bb® and Bb endophyte did not control the aphids in 2017. However, in 2018 the best aphid control resulted from the biopesticides used. In 2017 plots treated with Eco-Bb® had the lowest number of thrips, while in 2018 plots treated with Bandit® had the least thrips, followed by treatments with M. rileyi and Karate®. There were no significant differences in the populations of whiteflies, however, insecticides were more effective than the biopesticides. All the treatments, except for Bandit®, significantly reduced the number of spider mites compared in 2017.Applications of Eco-Bb® and Bb endophyte significantly reduced spider mites in 2017, while in 2018 plots treated with Karate®, followed by M. rileyi, resulted in the lowest number of spider mites. Application of Bb endophyte, Chlorpyrifos®, and Karate® resulted in the lowest number of cotton stainers. The highest mean cottonseed yields of 6395 kg ha−1, 6295 kg ha−1, and 6141 kg ha−1 were recorded in plots sprayed with Bandit®, Bb endophyte, and Eco-Bb®, respectively. Biopesticides and chemical insecticides can be combined or alternated for future IPM programmes to control cotton pests.