An automatic balancing valve is described provided with a valve body having at least one inlet channel and an outlet channel for a heat transfer fluid, wherein the flow regulation is carried out by a ball shutter having an axial through channel with axis perpendicular to the rotation axis of the ball. The ball valve has at least one radial channel aligned with the rotation axis of the ball and is connected to the axial through channel. The radial channel has an outlet port having a circular cross-section which hydraulically connects the axial through channel of the ball with the outlet channel of the valve.