The discrepancy between experimental and theoretical total electron-impact ionization cross-sections of the fluorides CFx and NFx (x = 1-3) is attributed to inadequacies in previous theoretical models. Cross-sections calculated using a recently developed siBED model that takes into account the shielding of the long-range dipole potential in the collision are in agreement with experiment. The present study also re-analyzed the previously reported experimental data to account for incomplete collection of fragment ions and the presence of ion-pair formation channels. For NF3, Our experimental and theoretical cross-sections compare well with the recent data of Haaland et al. in the region below dication formation. (C) 2002 Elsevier Science B.V. All rights reserved.