Barnstable County Power Outage History
2014–2025 · Massachusetts
Worse than average — more frequent or longer outages than most counties. How grades are calculated
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 hrs | 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 |
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).
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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 |
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.