Partial miscibility in binary systems {N-methylpiperidine–water} and {2-methylpiperidine–water} was studied. The temperatures of liquid–liquid separation were determined as function of composition using both calorimetric technique and phase equilibrium cell. The densities of {amine–water} mixtures were determined in the domain of total miscibility at temperatures between 288K and 338 K. Excess molar volumes were derived from experimental density data and fit to a Redlich–Kister polynomial.