A double-sided milling cutting insert comprising: a top side; a bottom side; a side surface; a first cutting edge arranged at an intersection of the top side and the side surface, a second cutting edge arranged at an intersection of the bottom side and the side surface, a first symmetry axis, and a reference plane extending perpendicular to the first symmetry axis and virtually dividing the cutting insert into two halves; each of the first and second cutting edges (5, 6) comprising three cutting edge portions which are subsequently useable by indexing, the cutting edge portions comprising a cutting corner, a main cutting edge adjacent to one side of the cutting corner, and a wiper edge adjacent to the other side of the cutting corner, the wiper edge being connected to the main cutting edge of an adjacent cutting edge portion by a transition edge portion, wherein the main cutting edge is inclined towards the reference plane with increasing distance from the cutting corner and the wiper edge is inclined towards the reference plane with increasing distance from the cutting corner such that each of the first and second cutting edges (5, 6) has the largest distance to the reference plane in the regions of the cutting corners, wherein the side surface comprises a plurality of main clearance surfaces adjacent to the respective main cutting edges, a plurality of secondary clearance surfaces adjacent to the respective wiper edges, and a plurality of curved corner surfaces adjacent to the respective cutting corners, characterized in that - in a direction from the top surface to the bottom surface - the curved corner surfaces adjacent to the cutting corners of the first cutting edge transform into the secondary clearance surfaces adjacent to the wiper edges of the second cutting edge via transitional surfaces such that the curved corner surfaces protrude further to the outside than the secondary clearance surfaces. a top side; a bottom side; a side surface; a first cutting edge arranged at an intersection of the top side and the side surface, a second cutting edge arranged at an intersection of the bottom side and the side surface, a first symmetry axis, and a reference plane extending perpendicular to the first symmetry axis and virtually dividing the cutting insert into two halves; each of the first and second cutting edges (5, 6) comprising three cutting edge portions which are subsequently useable by indexing, the cutting edge portions comprising a cutting corner, a main cutting edge adjacent to one side of the cutting corner, and a wiper edge adjacent to the other side of the cutting corner, the wiper edge being connected to the main cutting edge of an adjacent cutting edge portion by a transition edge portion, wherein the main cutting edge is inclined towards the reference plane with increasing distance from the cutting corner and the wiper edge is inclined towards the reference plane with increasing distance from the cutting corner such that each of the first and second cutting edges (5, 6) has the largest distance to the reference plane in the regions of the cutting corners, wherein the side surface comprises a plurality of main clearance surfaces adjacent to the respective main cutting edges, a plurality of secondary clearance surfaces adjacent to the respective wiper edges, and a plurality of curved corner surfaces adjacent to the respective cutting corners, characterized in that - in a direction from the top surface to the bottom surface - the curved corner surfaces adjacent to the cutting corners of the first cutting edge transform into the secondary clearance surfaces adjacent to the wiper edges of the second cutting edge via transitional surfaces such that the curved corner surfaces protrude further to the outside than the secondary clearance surfaces.