Earliness in cotton is a highly valued trait that allows the crop to dodge late-season stress and facilitates efficient harvesting, ultimately benefiting farmers with optimal yield.Understanding the genetics of these complex traits is a prelude to designing extra-early maturing cotton genotypes.Two crosses with six generations (ESS-20 x FLT-25 and S-32 x FLT-25: P1, P2, F1, F2, BC1P1, and BC1P2) and one cross with five generations (NNDC-30 x NNDC-47: P1, P2, F1, F2, and F2:3) were field-evaluated for ten earliness and plant architecture traits in cotton.ANOVA presented significant generational differences for most traits.The inadequacy of the Additive-Dominance (A-D) model in explaining trait inheritance using scaling and joint-scaling tests highlighted the presence of epistatic gene actions.Further, the anal. of gene action unveiled the predominance of dominance effect [h] and dominance x dominance [l] epistatic effect, influencing the expression of most traits.Contrasting signs of [h] and [l] effects for these traits suggested the occurrence of duplicate epistasis across crosses.Therefore, population improvement strategies and heterosis breeding could be effective in designing extra-early maturing genotypes.All traits exhibited quant. inheritance, with partial and overdominance favoring early maturity.Notably, days to flowering and boll opening, exhibited neg. heterosis, suggesting the efficient development of short-duration cotton hybrids.Besides, the study also predicted less than one gene block for the majority of traits, suggesting a significant role of complex non-allelic interaction in trait expression.These findings offer valuable insights for strategizing efficient breeding methods to develop early-maturing cotton genotypes.