Abstract Two experiments were carried out to study the influence of processing on maize starch availability in vitro (IVSA) and subsequently, the effects of inclusion of processed maize in piglet diets on digestibility and production traits of young piglets. Treatment of maize by extrusion or pressure cooking increased IVSA from ∼ 20 to 90%. Both ileal and faecal apparent digestibility coefficients of diets with processed maize were measured in 55 piglets from an age of 45 days. Maize processing did not affect faecal coefficients for the diets. Ileal digestibility coefficients of organic matter and nitrogen-free extract however were higher for the diet with the extruded maize ( P < 0.05). With the exception of cystine and proline, the digestibility of amino acids was not influenced by extrusion of maize. The results show that treatment of maize by extrusion or pressure cooking has no advantage for production traits for healthy piglets from 1 week after weaning onwards.