A series of multireference (MRD-CI) calculations are presented for the electronic states of ArH correlating with the atomic limits up to Ar(1S) + H* (n= 3), in order to provide transition energies corresponding to the possible Rydberg spectra of ArH. The computed transition energies for several2Π → A2∑+transitions are found to be in good agreement with experimentalT0values, with discrepancies that in every case are smaller than 0·1 eV.