In Sein und Zeit Heidegger makes several claims about the nature of ‘assertion’ [Aussage]. These claims are of particular philosophical interest: they illustrate, for example, important points of contact and divergence between Heidegger's work and philosophical movements including Kantianism, the early Analytic tradition and contemporary pragmatism. This article provides a new assessment of one of these claims: that assertion is connected to a ‘present-at-hand’ ontology. I also indicate how my analysis sets the stage for a new reading of Heidegger's further claim that assertion is an explanatorily derivative phenomenon. I begin with a loose overview of Heidegger's position and then develop a sharper formulation of the key premises. I go on to argue that existing treatments of the supposed link between assertion and the ‘present-at-hand’ are unsatisfactory, and advance a new, ‘methodological’, interpretation of that link. Finally, I sketch the implications of my interpretation for the further claim that assertion is explanatorily derivative.