Van der Waals interactions between the ground-state triplet O( 3P) atom and the closed-shell HCl molecule are investigated in the pre-reactive region. Three adiabatic (two of A″ symmetry and one of A′ symmetry) and four non-relativistic diabatic potential energy surfaces are obtained by combining a restricted open-shell coupled cluster approach with the multireference configuration interaction method. The lower A″ adiabatic potential surface has a single minimum (D e = 589 cm -1) for a linear O⋯HC1 configuration. The upper A″ potential has a weak (D e = 65 cm -1) minimum for a linear HCl⋯O configuration. The A′ adiabatic potential has a weak (124 cm -1) T-shaped minimum. Adiabatic potentials intersect once in the O⋯HCl linear configuration and twice in the linear HCl⋯O geometry. The role of electrostatic interactions in shaping these potentials is discussed. The effects of spin-orbit coupling on this interaction are also investigated assuming a constant value of the SO parameter.