IOU · Massachusetts · EIA 54913
NSTAR Electric Company
IOU · Massachusetts · 464K customers. According to the U.S. Energy Information Administration's EIA Form 861, reliability for 2023 shows SAIDI 190 minutes/customer.
Reliability verdict
NSTAR Electric Company shows above-average chronic reliability in 2023: 76 minutes SAIDI excluding major events (190 minutes including them) across 464K customers.
- 190 min
- SAIDI 2023
- 0.88
- SAIFI 2023
- 76 min
- SAIDI ex-MED
- 464K
- Customers
Chronic reliability judged on SAIDI excluding major event days when reported (IEEE 1366). Source: EIA Form 861 · August 2026.
Signature read: mid-cohort SAIDI between the 96 and 258 minute tercile cuts.
What mid-pack NSTAR Electric Company filings show
NSTAR Electric Company is an investor-owned utility operating in Massachusetts under EIA identifier 54913. It reports service to approximately 463,946 customer accounts and generated about $1.03 billion in annual electric revenue, with a service footprint spanning 289 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 NSTAR Electric Company customer experienced 189.8 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 0.88, putting the typical customer at roughly 1 distinct interruption that year. Strip out major event days (hurricanes, ice storms) and SAIDI falls to 75.6 minutes; the difference from the headline 189.8 shows how much of the outage total came from weather rather than everyday grid issues.
NSTAR Electric Company has 4 years of continuous EIA reporting on file (2020–2023), enough to read a real trend rather than a single-year snapshot. Over that window, SAIDI moved from 235.7 down to 189.8 minutes, a trend worth noting for anyone weighing capital investment outcomes.
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.
190 min/year per customer
Power-out minutes per year (2023)
SAIDI by year (2020-2023)
Minutes per customer-year · EIA Form 861
Year-by-year SAIDI for NSTAR Electric Company from the same EIA filings as the table below. Lower is better; major-event years can spike the headline figure.
NSTAR Electric Company SAIDI trend
NSTAR Electric Company vs the nationwide SAIDI distribution
Where this utility's headline SAIDI sits among every EIA Form 861 utility with a reported figure
190 Around the middle fewer outage minutes than 44% 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 NSTAR Electric Company sits on price vs. reliability
Among the 781 U.S. utilities large enough to report both revenue per customer and a recent outage record, NSTAR Electric Company charges more per customer than 29% of them, and is more reliable (lower SAIDI) than 48% of them, placing it in the quadrant where it pays less and is less reliable. Revenue per customer and outage minutes are independent figures: paying more does not guarantee fewer outages.
Revenue per customer: $2,220/year · Latest SAIDI: 189.8 minutes/year.
SAIDI 2023 breakdown: 189.8 minutes
Reliability Trend (2020–2023)
| Year | SAIDI (min) | SAIDI nMED | SAIFI | Customers |
|---|---|---|---|---|
| 2020 | 235.7 | 65.0 | 1.140 | 1,446,211 |
| 2021 | 640.8 | 75.8 | 1.098 | 1,450,541 |
| 2022 | 196.7 | 68.5 | 1.033 | 1,471,114 |
| 2023 | 189.8 | 75.6 | 0.884 | 1,307,124 |
SAIDI nMED = SAIDI without major event days. Source: EIA Form 861.
Service Area
NSTAR Electric Company serves 289 ZIP codes in Massachusetts.
Frequently Asked Questions
How reliable is NSTAR Electric Company?
NSTAR Electric Company had a SAIDI of 189.8 minutes in 2023 including major weather events, but 75.6 minutes excluding them (the industry-standard measure of routine reliability, so the gap traces back to a major storm that year, not a chronic issue). Leaving aside major weather events, that figure comes in under the national average, pointing to above-average reliability.
What type of utility is NSTAR Electric Company?
NSTAR Electric Company is classified as a IOU serving Massachusetts.
How many customers does NSTAR Electric Company serve?
NSTAR Electric Company serves approximately 463,946 customers in Massachusetts.
How has NSTAR Electric Company's reliability changed over time?
NSTAR Electric Company 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
- Massachusetts
- Customers
- 463,946
- Annual Revenue
- $1.03B
- EIA ID
- 54913
Explore
Utilities with similar EIA profiles
Two cross-state peer sets for NSTAR Electric Company. Same-state SAIDI neighbors stay in Read-with below; these neighborhoods are nearest other-state utilities with at least 10,000 reported customers.
Similar customer count
Nearest utilities by Form 861 customers (464K here), outside Massachusetts.
Similar chronic SAIDI
Nearest utilities by latest SAIDI minutes (189.8 here), outside Massachusetts, excluding the customer-peer set.
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.