Digital transformation is reshaping how firms operate across traditional industries. This study defines three comparable outcomes—Operational Efficiency (OEI), Revenue Efficiency (RER), and Customer Experience (CEF)—and benchmarks them in a cross-industry setting. Using firm-level data (n = 250) alongside sector indicators, we quantify associations between digital capabilities and performance while accounting for sector heterogeneity. Results show stronger OEI and CEF in data-intensive sectors, with wider dispersion in regulated or legacy-system-heavy domains. We integrate OEI, RER, and CEF into a Composite Performance Index (CPI) to compare maturity profiles across sectors and to highlight alignment between capabilities and realized outcomes. The findings suggest that technology adoption alone is insufficient; complementary workforce readiness and process redesign are essential to unlock value. For managers, CPI offers a practical benchmark to prioritize investments. For policymakers, interoperability and data-governance frictions emerge as key barriers. The study is observational, so residual confounding may remain despite controls. We emphasize transparent measurement and reproducibility and outline future directions, including longitudinal designs and validation of composite indices.