A high-frequency module includes a filter unit and first and second external connection terminals. The filter unit includes first and second terminals and a plurality of SAW resonators. The plurality of SAW resonators are connected to one another by connection conductors. A matching element is connected between the first terminal and the first external connection terminal, and a matching element is connected between the second terminal and the second external connection terminal. At least one of the matching elements is inductively coupled or capacitively coupled to at least one of the connection conductors located at a position such that at least one of the SAW resonators is interposed between the matching element and the connection conductor.

A ladder surface acoustic wave filter includes a series arm connecting an input terminal and an output terminal, at least one parallel arm connecting the series arm and a ground terminal, at least one series arm resonator provided in the series arm, and at least two parallel arm resonators provided in at least one parallel arm and connected to each other in series. In the ladder surface acoustic wave filter, a connection point between at least the two parallel resonators connected to each other in series is grounded through an inductor.

A filter has a pass band including a reception band which is a first band and a reception band which is a second band and has input terminals, an output terminal, a switch circuit including a common terminal and selection terminals, a series-arm resonator connected between the selection terminal and the input terminal, a series-arm resonator connected between the selection terminal and the input terminal, and an acoustic wave resonator connected between the common terminal and the output terminal.

A radio frequency module includes a module substrate, a plurality of passive components disposed on a main surface of the module substrate, and a filter component disposed over the plurality of passive components, wherein the filter component includes series arm resonators that constitute an acoustic wave filter, the series arm resonator is connected between the series arm resonators, and a region of the filter component formed with the series arm resonator does not overlap the plurality of passive components and at least a part of the other region of the filter component overlaps at least a part of each of the plurality of passive components in a plan view of the module substrate.

A longitudinally coupled resonator acoustic wave filter including IDT electrodes including a first IDT electrode and a second IDT electrode, and first and second reflectors, in which the IDT electrodes have respective hot-side comb-shaped electrodes and respective ground-side comb-shaped electrodes, the hot-side comb-shaped electrodes of the first IDT electrodes are electrically connected to at least one of the first and second reflectors, the second IDT electrodes are between the IDT electrode and the first reflector and between the IDT electrode and the second reflector respectively, the hot-side comb-shaped electrodes of the IDT electrodes are connected to one of an input end and an output end, and the hot-side comb-shaped electrodes of the IDT electrodes are connected to the other of the input end and the output end.