Susceptibilities of conserved charges such as baryon minus lepton number enter baryogenesis computations, since they provide the relationship between conserved charges and chemical potentials. Their next-to-leading order corrections are of order g, where g is a generic Standard Model coupling. They are due to soft Higgs boson exchange, and have been calculated recently, together with some order g2 corrections. Here we compute the complete g2 contributions. Close to the electroweak crossover the soft Higgs contribution is of order g2, and is determined by the non-perturbative physics at the magnetic screening scale.