Assuming the abc conjecture holds with ε = 1/6, we use elementary methods to show that only finitely many s-Cullen numbers are repunits, aside from two known infinite families. More precisely, only finitely many positive integers s, n, b, and q with s,b ≥ 2 and n,q ≥ 3 satisfy C_s,n = nsⁿ + 1 = (b^q–1)/(b–1).