A method of producing a cooling channel piston for an internal combustion engine having a cooling channel in its piston crown, wherein a piston lower section with piston bosses, piston pin bores and piston skirts attach to the piston crown, wherein a piston blank is first produced with a circumferential collar radially projecting in the area of the piston crown, wherein the collar is then formed over, wherein, a seating area for the collar is formed in a transition zone between the piston crown and the piston lower section and the collar is formed over in such a way until its outer radially circumferential edge comes very close to or butts completely against the seating area to form a closed cooling channel.