In this paper we investigate the cut-off effects at tree-level of perturbation theory for three different lattice regularizations of fermions –- maximally twisted mass Wilson, overlap and Creutz fermions. We show that all three kinds of fermions exhibit the expected O(a²) scaling behaviour in the lattice spacing. Moreover, the size of these cut-off effects for the considered quantities i.e. the pseudoscalar correlation function C_PS, the mass m_PS and the decay constant f_PS is comparable for all of them.

PACS numbers: 11.15.Ha, 12.38.Gc