March i/mɑrtʃ/ is the third month of the year in both the Julian and Gregorian calendars. It is one of seven months that are 31 days long. In the Northern Hemisphere, the meteorological beginning of spring occurs on the first day of March. The March equinox on the 20th or 21st marks the astronomical beginning of spring in the Northern Hemisphere and the beginning of autumn in the Southern Hemisphere, where September is the seasonal equivalent of the Northern Hemisphere's March.March starts on the same day of the week as November every year, and February in common years only. March ends on the same day of the week as June every year. In leap years, March starts on the same day as September and December of the previous year. In common years, March starts on the same day as June of the previous year. In leap years, March ends on the same day of the week as April and December of the previous year. In common years, March ends on the same day of the week as September of the previous year. In years immediately before leap years, March starts on the same day of the week as May of the following year. In years immediately before common years, March starts on the same day of the week as August of the previous year. In years immediately before leap years, March ends on the same day of the week as May of the following year. In years immediately before common years, March ends on the same day of the week as August and November of the following year.