An off-season South Pacific tropical cyclone is a tropical cyclone that exists in the South Pacific basin outside of the official tropical cyclone season. The World Meteorological Organization currently defines the season as occurring between November 1 and April 30, of the following year, with approximately 96% of all activity occurring between these months. If a tropical cyclone should develop during the off-season, it is more likely to develop during May or October than any other month of the off-season. As of 2018, there have been 91 tropical cyclones known to have occurred off-season, with 54 of these occurring since the satellite era started during the 1969–70 season.