The interface character distributions (ICDs) of cold-rolled and annealed duplex stainless steel specimens, previously solid-solution-heated (SHT) at 1573 K and 1323 K, are investigated using electron backscatter diffraction (EBSD) and five-parameter analysis (FPA). For the δ-ferrite phase, high concentrations of low angle grain boundaries (LAGBs) are developed, and the boundary planes are predominantly oriented on {111}. High angle grain boundaries (HAGBs) with misorientations ranging from 50 to 60° are mostly pure tilt boundaries, and the boundary planes are primarily located on {112}. For the austenite phase, very high density of coherent twin boundaries are introduced, implying that the boundary planes are exactly oriented on {111}. The phase boundary character distribution (PBPD) appears to be connected with the K-S and N-W orientation relationships (ORs) terminating on {110} ‖{111} and {110}‖{hkl}, respectively.