We present a comprehensive study of X-ray emission and wind properties of magnetic early B-type stars. We compile the complete sample of early B-type stars with detected magnetic fields to date and existing X-ray measurements, in order to study whether the X-ray emission can be used as a general proxy for stellar magnetism. For the first time we analyze the UV spectra of B stars with magnetic fields by means of non-LTE iron-blanketed stellar atmosphere model that account for the X-rays at the intensity and temperatures observed. The mass-loss rates inferred from the analysis of UV lines are significantly lower than predicted by hydrodynamically consistent models. We find that the X-ray properties of early B-type magnetic stars are diverse, and that hard and strong X-ray emission does not necessarily correlate with the presence of a magnetic field.