Barnstable CountyPower Outage History
What this grade means
Worse than average — more frequent or longer outages than most counties. This county's recorded history shows more frequent outages and/or longer restoration times than most US counties over the same 12-year period. If you live here, it's worth taking backup power more seriously than an average household would.
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Oct 27, 2021 | 21 hrs | 273,634 (72%) | High Wind |
| Oct 27, 2021 | 16 hrs | 146,472 (38%) | High Wind |
| Oct 27, 2021 | <1 hr | 136,684 (36%) | High Wind |
| Mar 13, 2018 | 67 hrs | 128,268 (34%) | Strong Wind |
| Mar 2, 2018 | 81 hrs | 103,060 (27%) | High Wind |
Was There an Outage on a Specific Date?
Pick a date to see whether a power outage was recorded for Barnstable County, Massachusetts that day.
Over the 12 years from 2014 to 2025, Barnstable County recorded 1,682 distinct power outage events, averaging 2.4 hours per event.
The single worst outage on record in Barnstable County started October 27, 2021 (High Wind), lasting 21 hours and leaving up to 273,634 customers without power (72% of the county) at its peak.
July has historically been the worst month for outages in Barnstable County, with 206 events recorded during that month across the dataset.
Based on this history, Barnstable County earns a Reliability Grade of D, placing it in the 37th percentile nationally for grid reliability (higher percentile = more reliable).
Similar counties in Massachusetts
Counties with the closest reliability grade and national percentile to Barnstable County.
| County | Grade | National percentile |
|---|---|---|
| Plymouth County | C | 47th |
| Nantucket County | C | 47th |
| Essex County | C | 50th |
| Worcester County | C | 55th |
| Middlesex County | B | 64th |
Most reliable counties nationally
The top 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | South Dakota | A | 100th |
| Clearwater County | Minnesota | A | 99th |
| Limestone County | Alabama | A | 99th |
Least reliable counties nationally
The bottom 3 counties nationally by reliability grade and percentile.
| County | State | Grade | National percentile |
|---|---|---|---|
| Clay County | West Virginia | F | 0th |
| Lincoln County | West Virginia | F | 0th |
| Cameron Parish | Louisiana | F | 0th |
FAQ
How often does power go out in Barnstable County?
Between 2014 and 2025, Barnstable County recorded 1,682 outage events, averaging 2.4 hours each.
What is Barnstable County's reliability grade?
Barnstable County has a Reliability Grade of D, in the 37th national percentile.
What was the worst power outage in Barnstable County?
The worst outage on record started October 27, 2021 (High Wind), lasting 21 hours and affecting up to 273,634 customers.