Full Moon In September 2025. For northern hemisphere dwellers, september's full moon was the harvest moon. The september 2025 full moon will be on tuesday september 17, 2025 10:34 pm edt or september 18, 2025 2:34 am utc.

On september 17/18 the sunlit lunar nearside passed into shadow, just grazing earth’s umbra,. Explore this september moon phase calendar by clicking on each day to see detailed information on that days phase.