The polarization properties of a solid cube-corner reflector, using total internal reflection, are analysed using some general properties of the Jones matrices. This description leads to the conclusion that all non-absorbing systems, including the cube-corner, may be considered as a single linear retarder with suitable relative rotation between input and output reference axes. Simple analytical results are obtained for the case of normal incidence, and, in particular, it is shown that a cube-corner of refractive index 1.76476 functions as a 90° retarder. Results of numerical calculations for non-normal incidence are summarized. The analysis presented contrasts with the determination of elliptically polarized eigenstates, as given by Peck, and has proved particularly useful when incorporating cube-corner reflectors in interferometers.