Deep space optical communication is a highly efficient alternative to radio frequency (RF) technology offering higher data bandwidths. The challenge is that deep space optical communication is photon limited. Rejection of extraneous light is critical to maximizing signal quality. High transmitting, ultra-narrow bandpass filters with high out of band optical density (OD) can meet this requirement while improving signal throughput. Design trade-offs and fabrication results are presented for ultra-narrow bandpass filters with bandwidths as narrow as 0.2 nm full width half maximum (FWHM) with on-band transmission greater than 95% and off band rejection of greater that OD 5. Filters are designed to match laser wavelengths in the region of 1550 nm.