During the 1990-91 and 1991-92 seasons planting date experiments were carried out at Narrabri Agricultural Research Station using a range of cotton varieties. These experiments form part of an on-going program to investigate the agronomic performance of new cotton genotypes and they also provide data for the development of crop simulation models. This paper presents the yield results from these experiments and draws conclusions about the most appropriate varieties for planting in various pans of the season.