Let G be a reductive p-adic group and let H(G) s be a Bernstein block of the Hecke algebra of G. We consider two important topological completions of H(G) s : a direct summand S(G) s of the Harish-Chandra-Schwartz algebra of G and a two-sided ideal C * r (G) s of the reduced C * -algebra of G. These are useful for the study of all tempered smooth G-representations.We suppose that H(G) s is Morita equivalent to an affine Hecke algebra H(R, q) -as is known in many cases. The latter algebra also has a Schwartz completion S(R, q) and a C * -completion C * r (R, q), both defined in terms of the underlying root datum R and the parameters q.We prove that, under some mild conditions, a Morita equivalence H(G) s ∼M H(R, q) extends to Morita equivalences S(G) s ∼M S(R, q) and C * r (G) s ∼M C * r (R, q). We also check that our conditions are fulfilled in all known cases of such Morita equivalences between Hecke algebras. This is applied to compute the topological K-theory of the reduced C * -algebra of a classical p-adic group.