IOU · Arizona · EIA 19728

UNS Electric, Inc

IOU · Arizona · 106K customers. According to the U.S. Energy Information Administration's EIA Form 861, reliability for 2023 shows SAIDI 165 minutes/customer.

Reliability verdict

UNS Electric, Inc shows above-average chronic reliability in 2023: 44 minutes SAIDI excluding major events (165 minutes including them) across 106K customers.

165 min
SAIDI 2023
0.78
SAIFI 2023
44 min
SAIDI ex-MED
106K
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: mid-cohort SAIDI between the 96 and 258 minute tercile cuts.

What mid-pack UNS Electric, Inc filings show

UNS Electric, Inc is an investor-owned utility operating in Arizona under EIA identifier 19728. It reports service to approximately 106,045 customer accounts and generated about $0.25 billion in annual electric revenue, with a service footprint spanning 46 ZIP codes. Because it is investor-owned, the state public utility commission oversees its rate cases and reliability performance rather than a local board.

In 2023, the average UNS Electric, Inc customer experienced 164.8 minutes of power interruptions, a measure known as SAIDI, or 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. SAIFI, the average number of outage events per customer, was 0.78 for the same period, so customers statistically faced roughly 1 distinct interruption that year. Excluding major event days (hurricanes, ice storms), SAIDI drops to 44.1 minutes, the gap between that figure and the headline 164.8 reveals how much weather, not day-to-day infrastructure, drove outages.

With 4 consecutive years of EIA data (2020–2023), UNS Electric, Inc's reliability record can be judged on trend rather than one isolated year. SAIDI has increased from 43.2 to 164.8 minutes, which may reflect either worsening weather exposure or delayed grid modernization.

B-
Reliability Score
68/100
UNS Electric, Inc · 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 B+ 44.1 min/yr
SAIDI excluding major-event days — day-to-day grid performance
Total Outage Duration D 164.8 min/yr
SAIDI including storms and major events — the full-year experience
Outage Frequency B 0.78/yr
SAIFI — average number of interruptions per customer per year
SAIDI vs. national mean (341 min) 22.0%

165 min/year per customer

UNS Electric, Inc SAIDI

Power-out minutes per year (2023)

165 SAIDI165 SAIDINat. avg 341341SAIDI165SAIDI

Excellent

SAIDI by year (2020-2023)

Minutes per customer-year · EIA Form 861

Year-by-year SAIDI for UNS Electric, Inc 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

UNS Electric, Inc SAIDI trend

0 30 60 90 120 150 180 210 2020 2021 2022 2023 43.2 183.2 157 164.8
Year-by-year SAIDI from the same EIA filings as the table below. Lower is better; major-event years can spike the headline figure.

UNS Electric, Inc vs the nationwide SAIDI distribution

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

165 Lower than most fewer outage minutes than 50% 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 UNS Electric, Inc sits on price vs. reliability

Among the 781 U.S. utilities large enough to report both revenue per customer and a recent outage record, UNS Electric, Inc charges more per customer than 38% of them, and is more reliable (lower SAIDI) than 53% 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.

UNS Electric, Inc 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: 27Point, Price percentile: 3 · Reliability percentile: 35Point, Price percentile: 5 · Reliability percentile: 30Point, Price percentile: 8 · Reliability percentile: 77Point, Price percentile: 10 · Reliability percentile: 37Point, Price percentile: 13 · Reliability percentile: 90Point, Price percentile: 15 · Reliability percentile: 15Point, Price percentile: 18 · Reliability percentile: 22Point, Price percentile: 20 · Reliability percentile: 17Point, Price percentile: 23 · Reliability percentile: 75Point, Price percentile: 25 · Reliability percentile: 10Point, Price percentile: 28 · Reliability percentile: 47Point, Price percentile: 30 · Reliability percentile: 57Point, Price percentile: 33 · Reliability percentile: 55Point, Price percentile: 35 · Reliability percentile: 7Point, Price percentile: 38 · Reliability percentile: 2Point, Price percentile: 43 · Reliability percentile: 67Point, Price percentile: 45 · Reliability percentile: 45Point, Price percentile: 48 · Reliability percentile: 0Point, Price percentile: 50 · Reliability percentile: 12Point, Price percentile: 53 · Reliability percentile: 80Point, Price percentile: 55 · Reliability percentile: 85Point, Price percentile: 57 · Reliability percentile: 92Point, Price percentile: 60 · Reliability percentile: 72Point, Price percentile: 63 · Reliability percentile: 5Point, Price percentile: 65 · Reliability percentile: 65Point, Price percentile: 68 · Reliability percentile: 97Point, Price percentile: 70 · Reliability percentile: 70Point, Price percentile: 73 · Reliability percentile: 50Point, Price percentile: 75 · Reliability percentile: 43Point, Price percentile: 78 · Reliability percentile: 95Point, Price percentile: 80 · Reliability percentile: 20Point, Price percentile: 83 · Reliability percentile: 100Point, Price percentile: 85 · Reliability percentile: 32Point, Price percentile: 88 · Reliability percentile: 25Point, Price percentile: 90 · Reliability percentile: 82Point, Price percentile: 93 · Reliability percentile: 60Point, Price percentile: 95 · Reliability percentile: 87Point, Price percentile: 98 · Reliability percentile: 62Point, Price percentile: 100 · Reliability percentile: 52UNS Electric, Inc, Price percentile: 38 · Reliability percentile: 53
UNS Electric, Inc vs. a 40-utility national peer sample, price percentile vs. reliability percentile.

Revenue per customer: $2,337/year · Latest SAIDI: 164.8 minutes/year.

SAIDI 2023 breakdown: 164.8 minutes

Reliability Trend (2020–2023)

Year SAIDI (min) SAIDI nMED SAIFI Customers
2020 43.2 0.0 0.810 101,032
2021 183.2 48.5 1.050 102,667
2022 157.0 77.2 1.320 104,555
2023 164.8 44.1 0.776 105,267

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

Service Area

UNS Electric, Inc serves 46 ZIP codes in Arizona.

85344853578536085601856118561485621856228562485628856378564085645856468564885662860468630586321863228640186402864038640486405864068640986411864128641386426864298643086431864338643486436864378643886439864408644186442864438644486445

Frequently Asked Questions

How reliable is UNS Electric, Inc?

UNS Electric, Inc had a SAIDI of 164.8 minutes in 2023 including major weather events, but 44.1 minutes excluding them (the IEEE-standard day-to-day reliability measure, the difference points to a major storm that year rather than an ongoing problem). Excluding major weather events, this is below the national average, indicating above-average reliability.

What type of utility is UNS Electric, Inc?

UNS Electric, Inc is classified as a IOU serving Arizona.

How many customers does UNS Electric, Inc serve?

UNS Electric, Inc serves approximately 106,045 customers in Arizona.

How has UNS Electric, Inc's reliability changed over time?

UNS Electric, Inc 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
Arizona
Customers
106,045
Annual Revenue
$0.25B
EIA ID
19728

Utilities with similar EIA profiles

Two cross-state peer sets for UNS Electric, Inc. 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.