Abstract Costa Cabral and Canuto [B.J. Costa Cabral, S. Canuto, Chem. Phys. Lett. 406 (2005) 300] have studied the O–H bond dissociation enthalpy in water, hydrogen peroxide, methanol, phenol and catechol using a number of theoretical methods. Their choice of experimental O–H bond dissociation enthalpies for phenol and catechol are not the best available values and led them to several erroneous conclusions about the performance of methodologies they tested. In this work, we present more rigorous experimental O–H bond dissociation enthalpies for phenol and catechol and discuss the implications these data have on the conclusions presented by Costa Cabral and Canuto. We also demonstrate the importance of the inclusion of higher-order excitations in the coupled-cluster treatment of bond dissociation enthalpy of the O–H bond in H 2O 2 and HOO .