Lysimachia × commixta is a hybrid of flowering plants in the primrose family Primulaceae.

Although it shows a floral morphology approaching L. thyrsiflora, the hybrid is often confused with L. terrestris, which also has a terminal raceme.

Lysimachia × commixta was first collected (as L. terrestris) by H. Eggert in 1878 in St. Clair County, Illinois.

The hybrid ranges from eastern Canada, across New England, New York, and the Great Lakes region, extending as far west as Minnesota.

The hybrid's expansion into southern Illinois is thought to be a result of vegetative propagation along the Mississippi River lowlands.