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We show that for any integer $s \geq 2$, there are only finitely many$s$-Cullen numbers that are repunits. More precisely, for fixed $s \ge 2$,there are only finitely many integers $n$, $b$, and $q$ with $n \geq 2$, $b\geq 2$ and $q \geq 3$ such that \[C_{n,s} = ns^n + 1 = \frac{b^q -1}{b-1}.\]The proof is elementary and effective, and it is used to show that there are no$s$-Cullen repunits, other than explicitly known ones, for all $s \in[2,8896]$.

Only finitely many $s$-Cullen numbers are repunits for a fixed $s\ge 2$