Disclosed herein are methods, systems, and computing devices for fitting bilateral hearing prostheses. An example method includes sending a signal to a first hearing prosthesis and a second hearing prosthesis. The signal causes the first hearing prosthesis to deliver a first stimulus to a body part in a left auditory pathway of a user. The signal also causes the second hearing prosthesis to deliver a second stimulus to a body part in a right auditory pathway of the user. The first stimulus and the second stimulus cause the user to perceive a sound and are delivered simultaneously. The method also includes receiving an indication of a perception of the sound by the user. The method further includes determining an adjustment to at least one of the first stimulus or the second stimulus based on the perception of the sound by the user.