We identify c. 7000 cal yr BP Tuhua Tephra in a marine sediment core from offshore eastern North Island, New Zealand. Its mineral assemblage includes aegirine, which is diagnostic for the Tuhua (Mayor Island) Volcanic Centre, and electron microprobe analyses of glass shards yield compositions close to published analyses of the tephra onshore, closer to the source. Associated radiocarbon ages on planktonic foraminifera from the core show that its age lies within the range previously determined for the caldera-forming event that generated Tuhua Tephra. This occurrence, >380 km southeast of the source, indicates that the dispersal of the ash was bi-directional, and that earlier estimates of this tephra's volume may be conservative.