The Eastern Coteau Conference is nestled in the Northeast Corner of South Dakota.  This conference spans from the far Northeast to include the town of Rosholt (Tri-State serves students in South Dakota, North Dakota, and Minnesota), West to Britton, South to the Willow Lake area, stretches and serves students in the Deuel School District (including MN student athletes), and back up to the Wilmot area.

Member schools include: Britton-Hecla, Florence, Henry, Great Plains Lutheran, Rosholt (Tri-State), Waubay, Summit, Waverly-South Shore, Wilmot, Clark-Willow Lake (FB Only), Deuel (FB Only), and Webster (FB Only).

Before becoming the ECC, the conference was the "Whetstone Valley Conference."