Horizontal area passes are used to finish machine flat surfaces more efficiently by using flat bottom cutters. Horizontal area passes are aimed towards cavities, while horizontal core passes start off the block and machine in from the side making them more suitable for core forms, whilst extending tool life.

Horizontal area and horizontal core machining both have similar smoothing characteristics to area clearance and can detect all flat surfaces on a part, with or without using boundaries. 

Should the user require to machine these flat areas with more than one pass, the passes can be axially (along the tool axis) offset by a user any number of times.