This paper presents an efficient tool path planning strategy for three-axis CNC machining using curvature based segmentation (CBS) of freeform surface from its representation in the form of a point cloud. Curvature parameters estimated over the point data are used to partition the surface into convex, concave, and saddle like regions. Grid based adaptive planar tool path planning strategy is developed to machine each region separately within its boundaries. In addition to the region by region machining, strategy to stitch the obtained regions is also developed to minimize the tool lifts and tool marks. The developed region based tool path planning strategy is compared with the point cloud based adaptive planar strategy, iso-scallop strategy and commercial software for parts with various complexities. The result shows significant improvement in terms of performance parameters viz. machining time, tool path length and code length while maintaining the desired part surface quality. The proposed method is also tested by machining a real surface and analyzing its surface quality.