The invention relates to ultrasonic welding of industrial fabrics. Specifically, the invention relates to methods for ultrasonically welding the seam area of industrial fabrics using a textured horn (20) and/or anvil (30). The fabric edges are overlapped as woven or one or both edges can have some warp or weft yams raveled out. The method involves ultrasonically bonding the overlapped fabric edges, reducing the caliper of the two stacked edges to match the body caliper of the fabric itself. The bonded area can then be perforated using laser or other mechanical means to produce a seam having the same woven texture and permeability (air and/or water) as the body of the fabric.