A baseband filter and upconverter with configurable efficiency for use in wireless transmitters is disclosed. In an exemplary embodiment, an apparatus is provided that includes a baseband filter having configurable efficiency, and an upconverter having configurable efficiency and coupled to the baseband filter. The baseband filter and upconverter are configured to operate at a first efficiency level in a first output power range and to operate at a second efficiency level in a second output power range.