The vapour pressure of cyclohexane was determined using comparative ebulliometry, with water as the reference, over the whole fluid range. The results have been correlated using smoothing equations based on the reversed temperature variable tau = 1 - T/Tc, where T is the temperature and Te is the critical temperature, and the standard deviations from these smoothing equations suggest that the vapour pressures p are internally consistent to 2.8 . 10(-7) p.