Why is the energy on my utility bill higher than site meters?

This article explains the possible reasons that lead to discrepancy between utility (electricity) bill and site power meters.

Here are the possible reasons,

Utilities often apply Distribution Loss Factors (DLF) and Marginal Loss Factors (MLF) to recover grid transmission and distribution losses. These adjustments can add approximately 5-10% and are usually shown on the bill.

Utility and site meters measure AC energy, while EV chargers often report DC energy delivered. AC‑to‑DC conversion typically introduces 5-10% efficiency losses.

If on‑site meters are installed downstream of a transformer and the utility meter is upstream, the utility reading will include transformer losses.

Differences in meter accuracy class, calibration or configuration can create small measurement gaps.