What Is a Leap Year, and When Is the Next One?
Updated September 13, 2026 · 3 min read
A leap year is a year with 366 days instead of 365. The extra day is 29 February, and it exists because the Earth does not orbit the sun in a whole number of days.
One orbit takes about 365.2422 days. A 365-day calendar therefore runs fast by just under six hours a year. Left alone, that error compounds: after a century the calendar is out by 24 days, and after 700 years you would be having a northern-hemisphere Christmas in autumn.
The rule, in full
Most people know the first line. There are three.
- Every year divisible by 4 is a leap year.
- Except years divisible by 100, which are not.
- Unless they are also divisible by 400, which are.
So 2024 was a leap year. 1900 was not. 2000 was.
That third clause is the one that catches people — and software. 2000 being a leap year is the reason a lot of date bugs slept through the year 2000 and only surfaced later.
Why the rule has three parts
Adding a day every four years over-corrects. It assumes the year is 365.25 days long, which is 11 minutes too generous — an error of about three days every 400 years.
Skipping three leap years per 400 (the century years that are not divisible by 400) cancels almost all of it. The Gregorian average lands on 365.2425 days against the true 365.2422, leaving an error of roughly one day every 3,200 years. Good enough that nobody has needed to fix it since 1582.
The next leap years
2024, 2028, 2032, 2036, 2040, 2044, 2048, 2052, 2056, 2060
The next leap day is 29 February 2028, which falls on a Tuesday. After that comes Sunday 29 February 2032, then Friday 29 February 2036. There is a live countdown to 29 February if you want the exact number of days.
The next skipped leap year is 2100 — divisible by 4 and by 100, but not by 400, so February will have 28 days and the gap between leap days will be eight years rather than four.
If you were born on 29 February
Roughly 5 million people worldwide have a leap-day birthday — about 1 in 1,461. In non-leap years, the legal convention varies:
- In the UK and New Zealand, someone born on 29 February legally turns a year older on 1 March.
- In the US, most states leave it to the individual, and administrative systems usually default to 28 February.
- In Taiwan and Hong Kong, the legal birthday is 28 February.
Our date pages follow the calendar rather than any legal convention: a fixed date of 29 February resolves to 28 February in common years, and the countdown page for 29 February skips to the next real leap day.
Other kinds of leap
The calendar is not the only thing that gets patched.
- Leap seconds are added to UTC when the Earth's rotation drifts from atomic time — 27 have been added since 1972, and the practice is due to be discontinued by 2035.
- Leap months exist in lunisolar calendars. The Chinese calendar inserts a whole extra month roughly every three years, which is part of why Chinese New Year swings between 21 January and 20 February.
Quick answers
Is 2026 a leap year? No. 2026 is not divisible by 4. The next leap year is 2028.
Why is February the short month? It is the leftover. The Roman calendar's year originally began in March, and February — the last month — absorbed the days nobody else wanted. There is more on that in how many days are in each month.
How often is a leap year skipped? Three times every 400 years: 1700, 1800, 1900, then 2100, 2200, 2300.
Keep reading
- How Many Weeks Are in a Year?
A year has 52 weeks and 1 day — 52 weeks and 2 days in a leap year. Here's the exact figure, why some years have 53 numbered weeks, and what it means for school and work.
- Why Does Easter Change Date Every Year?
Easter moves because it is set by the moon, not the calendar. Here is the rule, the dates from 2026 to 2036, and why Orthodox Easter usually falls later.
- How Many Days Are in Each Month?
Seven months have 31 days, four have 30, and February has 28 or 29. Here's the full table, the knuckle trick for remembering it, and why February came up short.