A design structure, structure, and method for providing an on-chip variable delay transmission line with a fixed characteristic impedance. A method of manufacturing a transmission line structure includes forming a signal line of the transmission line structure, forming a first ground return structure that causes a first delay and a first characteristic impedance in the transmission line structure, and forming a second ground return structure that causes a second delay and a second characteristic impedance in the transmission line structure. The first delay is different from the second delay, and the first characteristic impedance is substantially the same as the second characteristic impedance.