January 31 is the 31st day of the year in the Gregorian calendar. It is the final day of January and, in a common year, there are 334 days remaining until the end of the year (335 in leap years).

As the last day of the first month, January 31 frequently serves as a cutoff for monthly statistics, financial reporting and administrative deadlines. In the Northern Hemisphere it falls in the middle of winter, while in the Southern Hemisphere it is a midsummer date; its seasonal significance therefore depends on location.

Calendar characteristics

January 31 always exists because January has 31 days, and its weekday shifts predictably from year to year. The pattern of weekday movement follows the ordinary passage of years and is influenced by the leap-year cycle, so the weekday on which January 31 falls advances in a repeating way across the calendar.

  • Last day of January: it precedes February 1 and sometimes marks transitions in billing or academic schedules.
  • Used in timekeeping and record-keeping: many monthly processes use January 31 as a natural reporting boundary.

History and name

The month of January is named for Janus, the Roman god of doors and beginnings. January itself was placed at the beginning of the calendar when the Roman calendar was reformed; January 31 is simply the terminal day of that month as fixed in the modern Gregorian system.

Uses, observances and notable associations

January 31 is not a universal public holiday, but various countries and communities may hold local events or observances on or around this date. It is commonly the birthdate or death date of historical figures and contemporary celebrities; for example, the composer Franz Schubert was born on January 31, and the entertainer Justin Timberlake also has this birthday. Many anniversaries and one-off historical events are recorded on this date in national chronologies.

Because it closes the first month, January 31 is often used in everyday life as a checkpoint: employers finalize payrolls, banks post month-end statements, researchers and meteorologists compile monthly summaries, and planners assess progress toward yearly goals.

Notable distinctions

  • It is always the last day of a month with 31 days.
  • Its role as month-end makes it common in administrative calendars worldwide.
  • Like any calendar date, it hosts a mix of cultural, historical and personal observances rather than a single universal significance.