The potential energy surface for the electronic ground state of He-HCO+ is calculated using ab initio QCISD(T) calculations. The frozen core potential energy surface is corrected using an improved variant of the adiabatical correction scheme. The resulting potentials have well depths of 281 cm(-1) for HCO+ (v(1) = 0) and 310 cm(-1) for HCO+ (v(1) = 1). Variational calculations are performed to assess spectroscopic observables. The dissociation energies are D-0 = 170 cm(-1) for HCO+ in its ground state, and D-0 = 185 cm(-1) in the v(1) = 1 state, and consume an appreciable amount of the well depth. The theoretically determined vibrational red shift of 15.4 cm(-1) is close to the experimental value of 12.4 cm(-1). It is proposed that the discrepancy originates mainly from the fact that the HCO+ bending is not included in the adiabatic correction.