IOU · Illinois · EIA 4110

Commonwealth Edison Co

IOU · Illinois · 3.2M customers. According to the U.S. Energy Information Administration's EIA Form 861, reliability for 2023 shows SAIDI 93 minutes/customer.

Reliability verdict

Commonwealth Edison Co shows above-average chronic reliability in 2023: 35 minutes SAIDI excluding major events (93 minutes including them) across 3.2M customers.

93 min
SAIDI 2023
0.61
SAIFI 2023
35 min
SAIDI ex-MED
3.2M
Customers

Chronic reliability judged on SAIDI excluding major event days when reported (IEEE 1366). Source: EIA Form 861 · August 2026.

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Signature read: short interruption minutes vs the 911 utility cohort (≤96 min tercile cut).

What short-outage Commonwealth Edison Co filings show

Commonwealth Edison Co is an 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). Excluding major weather events from that total, that places this utility well below the 120–180 minute national benchmark, signaling strong grid hardening and fast restoration practices. Over the same period, SAIFI (outage events per customer) was 0.61, putting the typical customer at 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 dropped from 341.1 to 93.3 minutes across that span, a direction regulators and prospective customers tend to watch closely.

B+
Reliability Score
78/100
Commonwealth Edison Co · 3 of 3 dimensions reported

Based on this utility's own EIA Form 861 reliability record -- baseline (major-event- excluded) outage duration, total outage duration, and outage frequency -- each benchmarked against every reporting utility nationwide. Not a measure of electricity rates or customer service, which this portal does not track.

Baseline Reliability A- 35.0 min/yr
SAIDI excluding major-event days — day-to-day grid performance
Total Outage Duration B- 93.3 min/yr
SAIDI including storms and major events — the full-year experience
Outage Frequency B+ 0.61/yr
SAIFI — average number of interruptions per customer per year
SAIDI vs. national mean (341 min) 12.4%

93 outage minutes per customer annually

Commonwealth Edison Co SAIDI

Annual minutes without electric service (2023)

93 SAIDI93 SAIDINat. avg 341341SAIDI93SAIDI

Excellent

SAIDI by year (2020-2023)

Minutes per customer-year · EIA Form 861

Year-by-year SAIDI for Commonwealth Edison Co from the same EIA filings as the table below. Lower is better; major-event years can spike the headline figure.

Source: U.S. EIA Form 861 As of August 2026

Commonwealth Edison Co SAIDI trend

0 50 100 150 200 250 300 350 2020 2021 2022 2023 341.1 101.6 65.8 93.3
Year-by-year SAIDI from the same EIA filings as the table below. Lower is better; major-event years can spike the headline figure.

Commonwealth Edison Co vs the nationwide SAIDI distribution

Where this utility's headline SAIDI sits among every EIA Form 861 utility with a reported figure

93 Lower than most fewer outage minutes than 68% of 911 utilities

Utilities nationwide, banded by latest reported SAIDI (minutes)

Each bar is a band; taller bars hold more utilities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source U.S. EIA Form 861 reliability filings · August 2026

Price vs. reliability

Where Commonwealth Edison Co sits on price vs. reliability

Among the 781 U.S. utilities large enough to report both revenue per customer and a recent outage record, Commonwealth Edison Co charges more per customer than 0% of them, and is more reliable (lower SAIDI) than 71% of them, placing it in the quadrant where it pays less while still being more reliable, the best-value quadrant. Revenue per customer and outage minutes are independent figures: paying more does not guarantee fewer outages.

Commonwealth Edison Co vs. a 40-utility national peer sample, price percentile vs. reliability percentile. Scatter plot of 41 data points (bubble-sized by third dimension). 050100150 050100150 Best valuePays for itCheap + riskyWorst deal Price percentile Reliability percentile Point, Price percentile: 0 · Reliability percentile: 25Point, Price percentile: 5 · Reliability percentile: 15Point, Price percentile: 8 · Reliability percentile: 5Point, Price percentile: 10 · Reliability percentile: 17Point, Price percentile: 13 · Reliability percentile: 77Point, Price percentile: 15 · Reliability percentile: 97Point, Price percentile: 18 · Reliability percentile: 12Point, Price percentile: 20 · Reliability percentile: 52Point, Price percentile: 23 · Reliability percentile: 10Point, Price percentile: 25 · Reliability percentile: 27Point, Price percentile: 28 · Reliability percentile: 47Point, Price percentile: 30 · Reliability percentile: 100Point, Price percentile: 33 · Reliability percentile: 35Point, Price percentile: 35 · Reliability percentile: 60Point, Price percentile: 38 · Reliability percentile: 32Point, Price percentile: 40 · Reliability percentile: 37Point, Price percentile: 43 · Reliability percentile: 65Point, Price percentile: 45 · Reliability percentile: 43Point, Price percentile: 48 · Reliability percentile: 0Point, Price percentile: 50 · Reliability percentile: 7Point, Price percentile: 53 · Reliability percentile: 75Point, Price percentile: 55 · Reliability percentile: 82Point, Price percentile: 57 · Reliability percentile: 87Point, Price percentile: 60 · Reliability percentile: 72Point, Price percentile: 63 · Reliability percentile: 2Point, Price percentile: 65 · Reliability percentile: 62Point, Price percentile: 68 · Reliability percentile: 92Point, Price percentile: 70 · Reliability percentile: 70Point, Price percentile: 73 · Reliability percentile: 45Point, Price percentile: 75 · Reliability percentile: 40Point, Price percentile: 78 · Reliability percentile: 90Point, Price percentile: 80 · Reliability percentile: 20Point, Price percentile: 83 · Reliability percentile: 95Point, Price percentile: 85 · Reliability percentile: 30Point, Price percentile: 88 · Reliability percentile: 22Point, Price percentile: 90 · Reliability percentile: 80Point, Price percentile: 93 · Reliability percentile: 55Point, Price percentile: 95 · Reliability percentile: 85Point, Price percentile: 98 · Reliability percentile: 57Point, Price percentile: 100 · Reliability percentile: 50Commonwealth Edison Co, Price percentile: 0 · Reliability percentile: 71
Commonwealth Edison Co vs. a 40-utility national peer sample, price percentile vs. reliability percentile.

Revenue per customer: $1,253/year · Latest SAIDI: 93.3 minutes/year.

SAIDI 2023 breakdown: 93.3 minutes

Reliability Trend (2020–2023)

Year SAIDI (min) SAIDI nMED SAIFI Customers
2020 341.1 40.0 0.830 4,153,856
2021 101.6 43.5 0.770 4,175,582
2022 65.8 37.6 0.630 4,194,257
2023 93.3 35.0 0.610 4,210,328

SAIDI nMED = SAIDI without major event days. Source: EIA Form 861.

Service Area

Commonwealth Edison Co serves 500 ZIP codes in Illinois.

6000160002600046000560006600076000860009600106001160012600136001460015600166001760018600196002060021600226002560026600296003060031600336003460035600376003860039600406004160042600436004460045600466004760048600506005160053600556005660060600616006260064600656006760068600696007060071600726007360074600756007660077600786007960081600826008360084600856008660087600886008960090600916009360094600956009660097600986009960101601026010360104601056010660107601086010960110601116011260113601156011660117601186011960120601216012260123601246012660128601296013060131601326013360134601356013660137601386013960140601416014260143601446014560146601476014860150601516015260153601546015560156601576015960160601616016260163601646016560168601696017060171601726017360174601756017660177601786017960180601816018360184601856018660187601886018960190601916019260193601946019560196601976019960201602026020360204602086020960290603016030260303603046030560399604016040260403604046040660407604086040960410604116041260415604166041760419 and 300 more

Frequently Asked Questions

How reliable is Commonwealth Edison Co?

Commonwealth Edison Co had a SAIDI of 93.3 minutes in 2023 including major weather events, but 35.0 minutes excluding them (the IEEE-standard measure of day-to-day reliability, the gap reflects a major storm that year, not chronic performance). Excluding major weather events, this is below the national average, indicating above-average reliability.

What type of utility is Commonwealth Edison Co?

Commonwealth Edison Co is classified as a IOU serving Illinois.

How many customers does Commonwealth Edison Co serve?

Commonwealth Edison Co serves approximately 3,242,491 customers in Illinois.

How has Commonwealth Edison Co's reliability changed over time?

Commonwealth Edison Co has 4 years of reliability data (2020-2023). This utility's SAIDI has stayed fairly flat over the period. Review the trend table above for year-by-year detail.

Utility Profile

Type
IOU
State
Illinois
Customers
3,242,491
Annual Revenue
$4.06B
EIA ID
4110

Utilities with similar EIA profiles

Two cross-state peer sets for Commonwealth Edison Co. Same-state SAIDI neighbors stay in Read-with below; these neighborhoods are nearest other-state utilities with at least 10,000 reported customers.

Source: U.S. Energy Information Administration Form 861 annual electric power industry survey · ZIP service territory: OpenEI. Disclaimer: informational only, not professional advice. See full disclaimer · methodology.