It is known that resonance decays influence the shape of the charge-balance functions measured in hadronic collisions. That is reflected in their rapidity and azimuthal widths and the integral and, therefore, has consequences for different model interpretations. In this paper, we show that the contribution from neutral resonance decays can be removed from the balance function in an analytical way, and test the performance of the removal procedure with PYTHIA events. Prospects for applications of the procedure to real-data analysis of balance functions are also discussed.