A surgical instrument end effector assembly includes a first jaw member and a second jaw member. The second jaw member includes an ultrasonic blade body and first and second electrodes disposed on either side of the ultrasonic blade body and extending longitudinally along a majority of a length of the ultrasonic blade body. The ultrasonic blade body is adapted to receive ultrasonic energy from an ultrasonic waveguide. The first and second electrodes taper in width proximally to distally and are adapted to connect to a source of electrosurgical energy. The first jaw member is movable relative to the second jaw member between a spaced-apart position and an approximated position for grasping tissue therebetween.