February 28 — position in the calendar and common-year observances

Calendar position and leap-year rules

Under the modern system, leap years occur on a roughly four-year cycle to keep the calendar aligned with Earth's orbit; this adjustment is explained in descriptions of leap years. In a common year February has 28 days, so February 28 is the month's last date. In years with an inserted leap day the month has 29 days, and February 28 precedes that extra day rather than closing the month. The distinction matters for computing intervals, deadlines, anniversaries and for software that calculates dates.

Legal and civil considerations

Civil law and administrative practice sometimes treat the date of a person's birth or the date when someone attains a legal age differently depending on whether a leap day exists that year. People born on February 29 commonly celebrate their birthday in non-leap years either on February 28 or on March 1; which day counts for formal age-related milestones is determined by national or regional statutes and by specific institutional rules. Conversely, those born on February 28 reach each annual birthday on that same calendar date every year.

Uses, observances and notable facts

February 28 often serves as an end-of-period deadline for monthly accounting, government reporting and subscription cycles simply because it is the last day of the month in common years. In cultural terms the day has no single global festival attached to it, but it can be associated with local events, memorials and anniversaries. Because its position shifts only when a leap day intervenes, it is a convenient fixed point when comparing dates across years or when describing seasonal timing: in the Northern Hemisphere it generally falls near the end of winter, and in the Southern Hemisphere near the end of summer.

Distinctions and practical notes

• February 28 is always day 59 of the year whether the year is leap or not; only the number of remaining days differs.
• Administrative rules about birthdays and legal ages vary; some authorities explicitly name February 28 as the day to use for people born on February 29, others specify March 1, and some leave it to courts or agencies to decide.
• When programming or converting dates, pay attention to calendar rules and to whether systems count days from zero or one, since off-by-one errors commonly appear around month-ends.

For compact explanations of related terms and calendar mechanics, see brief entries on the Gregorian calendar, the general concept of leap years and the distinction between a common year and a leap year.