The dispersion relations of parallel propagating modes (Langmuir mode, right and left handed circular polarized waves) in the weak magnetic field limit |ω − κ · ν| ≫ Ω are considered for ultra-relativistic arbitrary degenerate electron plasma. The results are presented in terms of moments of Fermi–Dirac distribution. The increase in the electron equilibrium number density from negative large (weakly degenerate) to positive large (highly degenerate) values of μ/Te is observed (where μ is the electron chemical potential and Te is the electron thermal energy). As a result, shifting of the cutoff points in all the real dispersion branches towards the higher values and increasing in the band gap between unmagnetized longitudinal and transverse modes in k-space are examined. Also, the suppression of the weak magnetic field effects in weakly magnetized right handed and left handed circular polarized waves and a decrease in the longitudinal and transverse screening effects are observed in the graphical patterns due to an increase in the equilibrium number density.