Since the 2022 election, it includes the counties of Butte, Colusa, Glenn, Lassen, Modoc, Shasta, Siskiyou, Sutter, and Tehama, and most of Yuba County.
Following the 2022 electoral process, this region comprises the counties of Butte, Colusa, Glenn, Lassen, Modoc, Shasta, Siskiyou, Sutter, and Tehama, as well as a significant portion of Yuba County.