Abstract We discuss possible effects of “meson-meson” and “baryon-antibaryon” Fock components to the pseudoscalar meson light-front wave functions. We include pseudoscalar-vector, pseudoscalarscalar, vector-vector and vector-axial meson-meson components and octet-octet, octet-decuplet and decuplet-decuplet baryon-antibaryon components. We find that only a few principal Fock components play an important role in the expansion. We estimate the probability of the four-quark components to be 10–26% and the probability of the six-quark components to be less than 0.3%. The presence of such Fock components leads to an extra non-perturbative sea in the pion. As a consequence, the sea quark distributions are larger than from the models with two valence quarks at the initial Q 2 scale. In analogy to the nucleon case, we find a suppression of the strange sea in the pion with respect to the light ( u , d ) quarks. This suppression factor exhibits a Bjorken- x dependence.