Moisture in cotton fibers affects physical properties such as length, strength, and processing properties. It is also a major factor in cotton garment comfort. Moisture absorption is improved by removing hydrophobic chemicals from the fiber primary wall. Cottons from various lots (varieties, growing location, and cultivation practices) may have different moisture properties. Moisture absorption is related to fiber internal structure and volume, which is largely determined by maturity. Maturity was determined on fibers of different variety and growing location. Selected samples were differentially dyed for maturity determinations. Mature and immature fibers were separated manually by color for comparison of moisture properties. Water of imbibition measurements showed that the most immature fibers had the highest water absorption. Initially, it had been expected that more mature fiber samples, those containing more secondary wall cellulose, would absorb more water than thin-walled immature fibers. Fiber surface structures are a possible reason for the higher water of imbibition of immature samples. These structures are being examined in relation to the maturity/moisture measurements.