Information on the effects of growing cotton ( Gossypium hirsutum L.)-based crop rotations on soil quality of dryland Vertisols is sparse. The objective of this study was to quantify the effects of growing cereal and leguminous crops in rotation with dryland cotton on physical and chemical properties of a grey Vertisol near Warra, SE Queensland, Australia. The experimental treatments, selected after consultations with local cotton growers, were continuous cotton (T 1), cotton–sorghum ( Sorghum bicolor (L.) Moench.) (T 2), cotton–wheat ( Triticum aestivum L.) double cropped (T 3), cotton–chickpea ( Cicer arietinum L.) double cropped followed by wheat (T 4) and cotton–wheat (T 5). From 1993 to 1996 land preparation was by chisel ploughing to about 0.2 m followed by two to four cultivations with a Gyral tyne cultivator. Thereafter all crops were sown with zero tillage except for cultivation with a chisel plough to about 0.07–0.1 m after cotton picking to control heliothis moth pupae. Soil was sampled from 1996 to 2004 and physical (air-filled porosity of oven-dried soil, an indicator of soil compaction; plastic limit; linear shrinkage; dispersion index) and chemical (pH in 0.01 M CaCl 2, organic carbon, exchangeable Ca, Mg, K and Na contents) properties measured. Crop rotation affected soil properties only with respect to exchangeable Na content and air-filled porosity. In the surface 0.15 m during 2000 and 2001 lowest air-filled porosity occurred with T 1 (average of 34.6 m 3/100 m 3) and the highest with T 3 (average of 38.9 m 3/100 m 3). Air-filled porosity decreased in the same depth between 1997 and 1998 from 45.0 to 36.1 m 3/100 m 3, presumably due to smearing and compaction caused by shallow cultivation in wet soil. In the subsoil, T 1 and T 2 frequently had lower air-filled porosity values in comparison with T 3, T 4 and T 5, particularly during the early stages of the experiment, although values under T 1 increased subsequently. In general, compaction was less under rotations which included a wheat crop (T 3, T 4, T 5). For example, average air-filled porosity (in m 3/100 m 3) in the 0.15–0.30 m depth from 1996 to 1999 was 19.8 with both T 1 and T 2, and 21.2 with T 3, 21.1 with T 4 and 21.5 with T 5. From 2000 to 2004, average air-filled porosity (in m 3/100 m 3) in the same depth was 21.3 with T 1, 19.0 with T 2, 19.8 with T 3, 20.0 with T 4 and 20.5 with T 5. The rotation which included chickpea (T 4) resulted in the lowest exchangeable Na content, although differences among rotations were small. Where only a cereal crop with a fibrous root system was sown in rotation with cotton (T 2, T 3, T 5) linear shrinkage in the 0.45–0.60 m depth was lower than in rotations, which included tap-rooted crops such as chickpea (T 4) or continuous cotton (T 1). Dispersion index and organic carbon decreased, and plastic limit increased with time. Soil organic carbon stocks decreased at a rate of 1.2 Mg/ha/year. Lowest average cotton lint yield occurred with T 2 (0.54 Mg/ha) and highest wheat yield with T 3 (2.8 Mg/ha). Rotations which include a wheat crop are more likely to result in better soil structure and cotton lint yield than cotton–sorghum or continuous cotton.