BULK ACOUSTIC WAVE FILTER

A bulk acoustic wave filter includes series resonators connected to a series arm, and parallel resonators connected to a parallel arm connected to the series arm. Two or more of the series resonators are disposed in parallel on the series arm, and each includes a substrate, a lower electrode on the substrate, a piezoelectric layer on the lower electrode, and an upper electrode on the piezoelectric layer, wherein, when an active region in which the lower electrode, the piezoelectric layer, and the upper electrode overlap each other is viewed from above, a centroid of the active region and a center of a rectangle defining an aspect ratio of the active region match each other, and when the active region is viewed from above, the active region has a shape of polygon symmetrical with respect to at least one axis passing through a center of the rectangle defining the aspect ratio.