The inclusive neutral and charged current deep inelastic scattering processes at high $Q^2$ provide the main basis for electroweak studies at HERA. These studies include the determination of the W boson propagator mass and weak neutral current couplings of light quarks to the $Z^0$ boson. The polarised electron or positron beam at HERA II gives rise to additional sensitivities for these studies. Exceptions also exist; this is the case for the single W production.