The biggest power outages in US history
The largest US power outages on record affected tens of millions of people. By customers affected in the federal DOE OE-417 record, the biggest single event is - Weather or natural disaster in 2023 (about 730,000 customers). Two records are shown below: the multi-decade federal disturbance filings, and the largest county-level outages in the modern EAGLE-I data (2014 onward).
Biggest US grid disturbances on record (DOE OE-417)
Federal emergency filings spanning decades — the record that captures the historic blackouts, ranked by customers affected.
| # | Event | Date | Area | Customers | Demand loss |
|---|---|---|---|---|---|
| 1 | - Weather or natural disaster | 2023-12-18 | ISO New England | 730,000 | — |
| 2 | Severe Weather | 2023-02-22 | Michigan: | 623,358 | 6,200 MW |
| 3 | Severe Weather | 2023-03-02 | Texas: Montague County, Cooke County, Grayson County, Fannin County, Lamar County, Young County, Jack County, Wise County, Denton County, Collin County, Hunt County, Delta County, Hopkins County, Stephens County, Palo Pinto County, Parker County, Tarrant County, Dallas County, Rockwall County, Kaufman County, Van Zandt County, Rains County, Eastland County, Erath County, Hood County, Somervell County, Johnson County, Ellis County, Henderson County, Comanche County, Mills County, Hamilton County, Bosque County, Hill County, Navarro County, Freestone County, Anderson County, Lampasas County, Coryell County, Bell County, McLennan County, Falls County, Limestone County, Leon County, Milam County, Robertson County; | 470,000 | — |
| 4 | Severe Weather | 2023-01-31 | Texas: Dallas County, Anderson County, Bosque County, Collin County, Comanche County, Cooke County, Delta County, Denton County, Ellis County, Erath County, Fannin County, Freestone County, Hamilton County, Henderson County, Hill County, Hood County, Hopkins County, Hunt County, Jack County, Johnson County, Kaufman County, Lamar County, Navarro County, Palo Pinto County, Parker County, Rains County, Red River County, Rockwall County, Somervell County, Tarrant County, Van Zandt County, Wichita County, Wise County; | 360,000 | — |
| 5 | Severe Weather | 2023-03-03 | Kentucky: Oldham County, Jefferson County, Fayette County, Franklin County, Hardin County, Hart County, Hopkins County, Jessamine County, Muhlenberg County, Nelson County, Scott County, Shelby County, Spencer County, Washington County, Woodford County, Bullitt County, Meade County, Lyon County, LaRue County, Henry County, Grayson County, Boyle County, Christian County, Anderson County; Virginia: Wise County; | 346,000 | — |
| 6 | Severe Weather | 2023-02-22 | Michigan: Van Buren County, Kalamazoo County, St. Joseph County, Calhoun County, Branch County, Hillsdale County, Jackson County, Washtenaw County, Monroe County, Lenawee County, Ingham County, Barry County, Allegan County, Ottawa County, Eaton County, Ingham County, Shiawassee County, Clinton County; | 261,043 | — |
| 7 | - Weather or natural disaster | 2023-07-26 | Michigan: Oakland County, Wayne County, Macomb County, Washtenaw County, Livingston County; | 246,000 | — |
| 8 | - Weather or natural disaster | — | Michigan: Oakland County, Wayne County, Macomb County, Washtenaw County, Livingston County; | 246,000 | — |
| 9 | - Generator loss or failure | 2023-12-16 | LUMA Energy | 230,330 | 220 MW |
| 10 | - Weather or natural disaster | 2023-07-18 | Tennessee: Shelby County; | 216,000 | 1,200 MW |
| 11 | - Weather or natural disaster | — | Tennessee: Shelby County; | 216,000 | 1,200 MW |
| 12 | Severe Weather | 2023-03-03 | Michigan: | 200,000 | 0 MW |
| 13 | - Weather or natural disaster | 2023-09-08 | Texas: Tarrant County, Dallas County; | 190,000 | — |
| 14 | Severe Weather | 2023-01-07 | California: Sacramento County; | 185,434 | 458 MW |
| 15 | Severe Weather | 2023-02-01 | Texas: Travis County; | 173,879 | 370 MW |
| 16 | - Generator loss or failure | 2023-12-18 | LUMA Energy | 170,316 | 115 MW |
| 17 | Severe Weather | 2023-04-29 | Texas: Hidalgo County, Cameron County, Willacy County, Starr County; | 168,419 | — |
| 18 | - Weather or natural disaster | — | Missouri: Kansas: | 163,156 | — |
| 19 | - Weather or natural disaster | 2023-07-14 | Missouri: Kansas: | 163,156 | — |
| 20 | Severe Weather | 2023-01-12 | Alabama: Georgia: | 162,000 | 1,158 MW |
| 21 | Severe Weather | 2023-03-25 | Ohio: West Virginia: Virginia: | 160,801 | — |
| 22 | Severe Weather | 2023-02-25 | California: Los Angeles County; | 153,555 | — |
| 23 | - Weather or natural disaster | 2023-10-04 | Texas: | 153,000 | — |
| 24 | - Weather or natural disaster | 2023-06-29 | Indiana | 140,000 | — |
| 25 | - Weather or natural disaster | 2023-09-24 | Texas: Dallas County, Tarrant County, McLennan County, Angelina County, Bell County, Williamson County, Smith County; | 130,000 | — |
Largest county outages since 2014 (EAGLE-I)
The biggest single county-level outage episodes in the modern record, by peak customers out. Click a county for its full outage history.
| # | County | Year | Peak customers out | Duration |
|---|---|---|---|---|
| 1 | Miami-Dade County, FL | 2017 | 1,777,800 | 38d 2h |
| 2 | Los Angeles County, CA | 2025 | 1,717,886 | 71d 4h |
| 3 | Harris County, TX | 2024 | 1,660,703 | 10d 20h |
| 4 | Broward County, FL | 2017 | 1,398,920 | 16d 15h |
| 5 | San Bernardino County, CA | 2025 | 1,383,556 | 8d 15h |
| 6 | Palm Beach County, FL | 2017 | 1,098,160 | 11d 14h |
| 7 | Ventura County, CA | 2025 | 1,077,693 | 8d 5h |
| 8 | Cochise County, AZ | 2024 | 718,642 | 1h 30m |
| 9 | Suffolk County, NY | 2025 | 599,357 | 20h 15m |
| 10 | Duval County, FL | 2017 | 528,830 | 16d 20h |
| 11 | Brevard County, FL | 2017 | 522,957 | 16d 16h |
| 12 | Hillsborough County, FL | 2024 | 520,308 | 30d 14h |
| 13 | King County, WA | 2024 | 518,386 | 53d 7h |
| 14 | Harris County, TX | 2024 | 502,077 | 41d 18h |
| 15 | Duval County, FL | 2016 | 467,041 | 4d 6h |
| 16 | Lee County, FL | 2017 | 462,570 | 17d 1h |
| 17 | Nassau County, NY | 2025 | 457,901 | 10h 45m |
| 18 | Lee County, FL | 2022 | 456,573 | 46d 20h |
| 19 | Harris County, TX | 2021 | 455,986 | 178d 9h |
| 20 | Pinellas County, FL | 2024 | 449,310 | 52d 17h |
| 21 | Pinellas County, FL | 2017 | 417,553 | 29d 2h |
| 22 | Collier County, FL | 2017 | 401,860 | 15d 1h |
| 23 | Dallas County, TX | 2024 | 386,856 | 37d 1h |
| 24 | Tarrant County, TX | 2021 | 367,316 | 16d 16h |
| 25 | Dallas County, TX | 2021 | 358,650 | 23d 19h |
| 26 | Plymouth County, MA | 2021 | 351,202 | 1d 23h |
| 27 | Sacramento County, CA | 2023 | 348,829 | 16d 6h |
| 28 | Sarasota County, FL | 2017 | 340,240 | 14d 23h |
| 29 | Orange County, FL | 2017 | 331,670 | 18d 1h |
| 30 | Los Angeles County, CA | 2025 | 331,150 | 1d 22h |
| 31 | Bexar County, TX | 2021 | 329,782 | 8d |
| 32 | Volusia County, FL | 2017 | 318,854 | 14d 5h |
| 33 | Brazoria County, TX | 2021 | 318,242 | 57d 16h |
| 34 | Dallas County, TX | 2019 | 313,327 | 40d 18h |
| 35 | Boone County, MO | 2019 | 311,925 | 6h 30m |
| 36 | Wayne County, MI | 2023 | 311,048 | 82d 14h |
| 37 | Harris County, TX | 2024 | 291,108 | 5d 17h |
| 38 | Monroe County, NY | 2018 | 284,600 | 15h |
| 39 | Cook County, IL | 2020 | 279,858 | 39d 18h |
| 40 | Travis County, TX | 2021 | 273,849 | 12d 22h |
Federal figures are DOE OE-417 emergency filings (customers affected as reported); modern county figures are from DOE/ORNL EAGLE-I and are never combined with the federal totals. See the methodology, the outage ranking by state, or which natural hazards drive outages.