Herznach-Ueken is a municipality in the district of Laufenburg in the canton of Aargau in Switzerland.

It was established on 1 January 2023 with the merger of the municipalities of Herznach and Ueken.

On 1 January 2023, the two municipalities of Herznach and Ueken merged to form the new municipality of Herznach-Ueken.

[1] The first blazon of the municipal coat of arms is Gules a Pitcher Vert lip dexter and handled Or.

The pitcher on the coat of arms is an attribute of Saint Verena to whom the chapel of Herznach is devoted.