Computations have been made for the maximum electric charge that a hydrometeor can retain in the ambient field of a thundrcloud. Two processes contribute to this limitation: water drop instability and corona discharge initiation. Solid hydrometeors are only affected by corona emission. Therefore, the numerical method presented here consists of computing the local electric field everywhere at the surface of the hydrometeor as a function of the ambient field and its net charge. When this surface field exceeds the corona onset at some point, as defined by Peek's law, the maximum charge is reached. For water drops the electric charge can be limited either by corona emission or by mechanical instability. The present model takes into account the influence of both drop rupture due to electrostatic pressure and corona emission. Dawson's experimental onset values are considered in this case. Since corona onset values are pressure dependent, so are the maximum charges of both kinds of hydrometeors. The computation results show that, at higher pressure, the maximum net charge of a solid, smooth hydrometeor is higher than that of a water drop of the same size located within the same ambient electric field. At lower pressure, this difference decreases. This preliminary work, in need of experimental confirmation, does not take into account temperature and purity of the particles but aims to reveal the relative parts played by the basic mechanisms in limiting net charge of the hydrometeors. ¿ American Geophysical Union 1989