Commonwealth Edison Co

What This Utility Data Tells You

Commonwealth Edison Co is a investor-owned utility operating in Illinois under EIA identifier 4110. It reports service to approximately 3,242,491 customer accounts and generated about $4.06 billion in annual electric revenue, with a service footprint spanning 500 ZIP codes. As an investor-owned utility, it operates under state public utility commission oversight that reviews rate cases and reliability performance.

In 2023, the average Commonwealth Edison Co customer experienced 93.3 minutes of power interruptions — a metric called SAIDI (System Average Interruption Duration Index). That places this utility well below the 120–180 minute national benchmark, signaling strong grid hardening and fast restoration practices. SAIFI — the average number of outage events per customer — was 0.61 for the same period, so customers statistically faced roughly 1 distinct interruption that year. Excluding major event days (hurricanes, ice storms), SAIDI drops to 35.0 minutes — the gap between that figure and the headline 93.3 reveals how much weather, not day-to-day infrastructure, drove outages.

The EIA dataset includes 4 years of continuous reporting (2020–2023) for Commonwealth Edison Co, which lets you see whether reliability is trending up or down rather than judging from a single snapshot. SAIDI has improved from 341.1 to 93.3 minutes over that window — a meaningful direction for prospective customers and regulators watching capital investment outcomes. All figures on this page come directly from EIA Form 861, the federal annual electric power industry survey, with service territory ZIPs sourced from OpenEI — you can cross-reference them with your own utility bill or use them when comparing providers before relocating.