An aerofoil has a main portion of aerofoil cross section, an inner spanwise root end where the aerofoil is in use secured to a supporting structure, and at an outermost spanwise end outboard of the main portion, beyond a tip station, a tip region which includes a tip edge. The planform configuration of the tip edge lies on a first Bezier curve constructed from at least four control points, P1, P2, P3 and P4, each lying on the periphery of a polygon which bounds the tip region. Control point P1 is located on a leading edge of the aerofoil. Control point P2 is located on the second side of the polygon. Control point P3 is located on the third side of the polygon, and control point P4 is located at the outermost tip edge point at a trailing edge of the aerofoil.