How Many Sundays Are in a Year? 52 or 53
A year holds 52 Sundays, or 53 when it starts on one. See which years get the extra Sunday and why the week-numbering standard disagrees.
A year contains 52 Sundays in most cases and 53 when the calendar lines up for it.
The Rule Behind Every Answer
A common year is 365 days. Divide by seven and you get 52 weeks with one day left over. That leftover day is the weekday January 1 falls on, and it is the only weekday that occurs 53 times.
A leap year is 366 days: 52 weeks plus two leftover days. Those are the weekdays of January 1 and January 2, and both occur 53 times.
So the answer is never a mystery. Look at what day the year starts on, check whether it is a leap year, and you have it.
Which Years Have 53 Sundays
A year has 53 Sundays when it begins on a Sunday, or when it is a leap year beginning on a Saturday.
- 2028 — leap year starting Saturday, so January 2 is a Sunday
- 2034 — common year starting Sunday
- 2040 — leap year starting Sunday
2026 begins on a Thursday, so it has 52 Sundays: the first on January 4, the last on December 27.
Sunday Is Both the First and Last Day of the Week
This is the one weekday where the counting question runs into a standards disagreement.
- Under ISO 8601, used across Europe and by most software, the week runs Monday to Sunday. Sunday closes the week.
- Under the US convention, the week runs Sunday to Saturday. Sunday opens it.
The number of Sundays in the year is identical either way — a calendar date has one weekday regardless of where you start counting. What changes is which *week number* a given Sunday belongs to, which can differ by one between the two systems. Our [week number calculator](/tools/week-number) uses the ISO rule.
2028 Is the Year to Watch
2028 is a leap year that begins on a Saturday. That gives it 53 Saturdays and 53 Sundays — 106 weekend days, the maximum any year can have. It happens roughly four times a century.
Practical Effects
Sunday counts matter for weekly rosters, places of worship planning an annual calendar, and any business whose week resets on Sunday night. A 53rd Sunday means one more cycle than a 52-week plan assumes.