Seismic probabilistic safety assessment (SPSA) is a systematic method for examining and evaluating the risk from earthquake-initiated accidents. The significant advances in the area of SPSA since the initial publication in 2002 of the NEA/CSNI Technical Opinion Paper (TOP) No. 2: Seismic Probabilistic Safety Assessment for Nuclear Facilities have prompted a revision of the document. The purpose of this revision is to provide the up-to-date international view on the state of the SPSA as it is currently being applied, including a description of the main elements of SPSA. The revision was written by seismic PSA experts of the NEA Working Group on Risk Assessment (WGRISK) member countries. The initial draft and subsequent updates were presented to WGRISK for review and comments. In addition, comments were obtained from seismic experts of the Working Group on External Events (WGEV) and Working Group on Integrity and Ageing of Components and Structures (WGIAGE).