The full moon in December 2025 occurs on Thursday, 4 December 2025.

Exact timing

  • The full moon reaches its peak illumination at about 23:14 UTC on 4 December 2025.
  • In Eastern Time (for example, New York), this corresponds to about 6:14 p.m. EST on the same date.

How long it looks “full”

  • The moon will appear full for roughly one day before and one day after the exact moment, so it will look very full from about 3–5 December 2025.
  • This December full moon is also known as the “Cold Moon” and is the last full moon of 2025.

TL;DR: When is full moon in December 2025? It’s on 4 December 2025, with the exact full phase around 23:14 UTC (evening of 4 December in North America).

Information gathered from public forums or data available on the internet and portrayed here.