| Rank | County | Production Period | Oil Production |
|---|---|---|---|
| #2 | Los Angeles County, CA | May 2026 | 555.4k BBLs |
| #3 | Ventura County, CA | May 2026 | 363.7k BBLs |
| #4 | Fresno County, CA | May 2026 | 295.6k BBLs |
| #5 | Monterey County, CA | May 2026 | 165k BBLs |
| #6 | Orange County, CA | May 2026 | 137.3k BBLs |
| #7 | Santa Barbara County, CA | May 2026 | 132.1k BBLs |
| #8 | San Luis Obispo County, CA | May 2026 | 43.7k BBLs |
| #9 | Kings County, CA | May 2026 | 2.7k BBLs |
| #10 | Tulare County, CA | May 2026 | 1.3k BBLs |
| #11 | Contra Costa County, CA | May 2026 | 1.2k BBLs |
| #12 | San Benito County, CA | May 2026 | 664 BBLs |
| #13 | San Bernardino County, CA | May 2026 | 476 BBLs |
| Rank | County | Production Period | Gas Production |
|---|---|---|---|
| #9 | Colusa County, CA | May 2026 | 105.6k MCF |
| #10 | Orange County, CA | May 2026 | 59.2k MCF |
| #11 | Sacramento County, CA | May 2026 | 55k MCF |
| #12 | Monterey County, CA | May 2026 | 45.9k MCF |
| #13 | Fresno County, CA | May 2026 | 38.1k MCF |
| #14 | Tehama County, CA | May 2026 | 25.4k MCF |
| #15 | Humboldt County, CA | May 2026 | 22.2k MCF |
| #16 | San Luis Obispo County, CA | May 2026 | 18.5k MCF |
| #17 | San Bernardino County, CA | May 2026 | 3.6k MCF |
| #18 | San Benito County, CA | May 2026 | 826 MCF |
| #19 | Santa Clara County, CA | May 2026 | 177 MCF |
| #20 | Yolo County, CA | May 2026 | 17 MCF |