Let Cn = [χ λ (µ)] λ,µ be the character table for Sn, where the indices λ and µ run over the p(n) many integer partitions of n. In this note we study Z ℓ (n), the number of zero entries χ λ (µ) in Cn, where λ is an ℓ-core partition of n. For every prime ℓ ≥ 5, we prove an asymptotic formula of the form. For primes ℓ and n > ℓ 6 /24, we show that χ λ (µ) = 0 whenever λ and µ are both ℓ-cores. Furthermore, if Z * ℓ (n) is the number of zero entries indexed by two ℓ-cores, then for ℓ ≥ 5 we obtain the asymptotic2020 Mathematics Subject Classification. 20C30, 11P82, 05A17. Key words and phrases. Primary: character tables, hook lengths, partitions, symmetric groups. E.M. acknowledges the support of a UVA Dean's Doctoral Fellowship. K.O. thanks the Thomas Jefferson Fund and the NSF (DMS-2002265 and DMS-2055118) for their support.1 This is a ``preproof'' accepted article for Canadian Mathematical Bulletin This version may be subject to change during the production process.