The Circulating Port Sub provides the ability to circulate above a stuck or plugged tool string. The Port Sub is equipped with rupture plugs that are activated by pumping a ball down the coiled tubing. Once the ball is on seat, an increase in pump pressure will cause the plug to rupture at the predetermined pressure, allowing circulation. The Circulating Port Sub is used with bottom hole assemblies in open hole completions or workovers utilizing downhole motors or other types of equipment.