Using a symmetry‐adapted linear augmented cylindrical wave method, the total band structures and the densities of states of the armchair single‐walled carbon nanotubes (SWNTs) (n,n) with 4 ≤ n ≤ 20, n = 30, 40, 60 and 100 are calculated. The approximations are made in the sense of muffin‐tin potentials and density functional theory only. The electronic states are presented as the functions of the two quantum numbers, namely, the continuous wave vector k corresponding to the screw symmetry operations and an integer rotational quantum number L between 0 and n – 1. An account of rotational and helical symmetry properties of the armchair SWNTs and particularly an introduction of the quantum number L permit to elaborate a more detailed classification of the armchair SWNTs electronic states. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)