PowerOutageHistory
Reliability Grade
C
Average
2014-2025
Ohio

Hamilton CountyPower Outage History

20142025 · Ohio
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What this grade means

Average — typical outage frequency and duration nationally. This county sits in the middle of the national distribution — its outage frequency and duration over the past 12 years are close to the nationwide median, neither notably better nor worse than most other US counties. A typical amount of backup-power preparedness is reasonable here.

Takeaway
Typical outage risk
Reliability Rank
Fuller bar = more reliable
Nationwide55th pct
In Ohio#43 of 88
See full Ohio rankings →
Total events
4,113
Recorded 2014–2025
Avg duration
2.3 hrs
Per outage event
Longest outage
82 hrs
Single worst event on record
Customers served
437,530
Utility customers in county

Outages by year

Outages by month (seasonality)

Worst outage events on record

DateDurationCustomers affectedCause
Sep 27, 202414 hrs70,272 (16%)Hurricane Helene
Nov 15, 201882 hrs66,555 (15%)Ice Storm
Jun 13, 202255 hrs57,698 (13%)Thunderstorm Wind
Jul 6, 202244 hrs57,136 (13%)Thunderstorm Wind
Aug 11, 20171 hrs47,938 (11%)Unnamed event

Was There an Outage on a Specific Date?

Pick a date to see whether a power outage was recorded for Hamilton County, Ohio that day.

Over the 12 years from 2014 to 2025, Hamilton County recorded 4,113 distinct power outage events, averaging 2.3 hours per event.

The single worst outage on record in Hamilton County started September 27, 2024 (Hurricane Helene), lasting 14 hours and leaving up to 70,272 customers without power (16% of the county) at its peak.

June has historically been the worst month for outages in Hamilton County, with 454 events recorded during that month across the dataset.

Based on this history, Hamilton County earns a Reliability Grade of C, placing it in the 55th percentile nationally for grid reliability (higher percentile = more reliable).

Similar counties in Ohio

Counties with the closest reliability grade and national percentile to Hamilton County.

CountyGradeNational percentile
Muskingum CountyC54th
Summit CountyC55th
Van Wert CountyC56th
Delaware CountyC56th
Franklin CountyC53rd

Most reliable counties nationally

The top 3 counties nationally by reliability grade and percentile.

CountyStateGradeNational percentile
Clay CountySouth DakotaA100th
Clearwater CountyMinnesotaA99th
Limestone CountyAlabamaA99th

Least reliable counties nationally

The bottom 3 counties nationally by reliability grade and percentile.

FAQ

How often does power go out in Hamilton County?

Between 2014 and 2025, Hamilton County recorded 4,113 outage events, averaging 2.3 hours each.

What is Hamilton County's reliability grade?

Hamilton County has a Reliability Grade of C, in the 55th national percentile.

What was the worst power outage in Hamilton County?

The worst outage on record started September 27, 2024 (Hurricane Helene), lasting 14 hours and affecting up to 70,272 customers.

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Data: ORNL EAGLE-I Recorded Electricity Outages (2014–2025), CC BY 4.0. Storm names: NOAA Storm Events Database. Last data refresh: 2025. See methodology.