The leading terms in the low‐frequency expansions for acoustically soft and hard bodies are examined and the relevance of the magnetic polarizability tensor is discussed. For a hard, rotationally symmetric body, two tensor elements, functions only of the geometry, are now sufficient to specify the entire low‐frequency scattering behavior in just the same way as the electrostatic capacity suffices for a soft body. Even these quantities are subject to known constraints and computed data for a variety of bodies are presented.