Abstract: In a capillary reference electrode with a capillary body which comprises a measuring chamber connected through an electrolytic bridge to a test sample which is adapted to be introduced into a capillary bore, the inlet orifice for the electrolyte is arranged at a point of the measuring chamber which is in a low position when the element is installed and the outlet orifice is arranged at a high position of the measuring chamber. The electrolytic bridge is formed through a communicating passage which has a substantially conical narrow end adjacent to the capillary bore with a very fine communication bore leading to the capillary bore. The resulting economy in electrolyte-consumption and absence of sensitivity in respect of potentially occuring air bubbles are further improved by providing the said communication bore with a substantially annular cross section.