The band structures and density of states (DOS) of all the three structural configurations of CsPbBr(3)without spin-orbit coupling (SOC = 0) and with the addition of spin-orbit coupling (SOC not equal 0) effects were calculated, using density functional theory. Upon the inclusion of the spin-orbit coupling, the bandgaps exhibit reductions of 1.27 eV, 1.16 eV and 1.08 eV for the cubic, tetragonal and orthorhombic phases, respectively. These calculations provide a positive split-off energy value of Delta(so) = 1.69 eV for the simple cubic phase. For the lower symmetry phases, thep-like fourfold degenerate Gamma((4))(8v) band has been observed to split to form two bands, in addition to the Gamma((2))(6v) split-off band. The calculated splitting energies between these bands are found to be in close agreement with previous experimentally measured values. The calculated electronic band structures show that CsPbBr(3)has a negative 'inversion energy' (Delta(i) < 0). The magnitude of the inversion energy for the cubic phase is 2.36 eV for SOC = 0, which increased by 0.4-2.76 eV with the addition of the spin-orbit coupling. The arrangement of Bloch levels in the band structure of CsPbBr3 has been found to resemble that of a typical topological semimetal, but with a nonzero bandgap opening, due to the presence of the inversion asymmetry within its molecular structure.