Abstract. Given any square matrix or a bounded operator A in a Hilbert space such that p(A) is normal (or similar to normal), we construct a Banach algebra, depending on the polynomial p , for which a simple functional calculus holds. When the polynomial is of degree d , then the algebra deals with continuous C d -valued functions, defined on the spectrum of p(A) . In particular, the calculus provides a natural approach to deal with nontrivial Jordan blocks and one does not need differentiability at such eigenvalues.Mathematics subject classification (2010): 15A60, 46J10, 47A60.