AbstractThe electrolytic conductivity of the polyelectrolytes poly(methacrylic acid), carboxymethyl‐cellulose, poly(vinylsulfonates), and poly(styrenesulfonates) was investigated. The concentration dependence of the equivalent conductivity was studied in detail and the limiting equivalent conductivity Λ0was determined. The rapid increase of the equivalent conductivity in dilute polyelectrolyte solutions, which is characteristic for most polyelectrolyte systems, was found to be due to decreased counterion binding in very dilute solutions. In this respect the behaviour of the poly(styrenesulfonate)s was exceptional, as their equivalent conductivities were practically constant down to limiting concentrations. Also, the poly(styrenesulfonic acid) clearly displayed specific hydrogen ion‐polyion interact