A compact, in-line polarization combiner uses a folded, reflective optical path from a first fiber to a second fiber. The combiner includes first and second fibers at one end of an in-line package, and a third fiber at the other end of the in-line package. A first polarization-dependent optical path is defined between the first and second fibers for light in a first polarization state. A second polarization-dependent path is defined between the first and third fibers for light in a second polarization state orthogonal to the first polarization state. A polarizer is disposed between the ends of the combiner and reflects light on the first path between the first and second fibers and transmits light on the second path between the first and third ports, A reflector is disposed on the first path to reflect light to the polarizer.