How Many Mondays Are in a Year? 52 or 53

A year has 52 Mondays, unless it starts on one — then it has 53.

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 Mondays

A year has 53 Mondays when it begins on a Monday, or when it is a leap year beginning on a Sunday.

• 2024 — leap year starting Monday
• 2029 — common year starting Monday
• 2035 — common year starting Monday
• 2040 — leap year starting Sunday, so January 2 is a Monday

2026 begins on a Thursday and has 52 Mondays, the first on January 5 and the last on December 28.

Monday Carries More Weight Than Other Weekdays

Monday is where most scheduling systems reset, so an extra one propagates further than an extra Saturday:

• Weekly meetings and sprint boundaries fire 53 times instead of 52.
• Monday-start ISO weeks mean a 53-Monday year usually has a week 53. The two are related but not identical — see [week numbers explained](/blog/week-numbers-explained).
• Rotas that assume a 52-week year drift by one full cycle.

Mondays and Working Days Are Different Counts

53 Mondays does not add a working day beyond the usual total. A common year has 261 weekdays regardless of which weekday is the extra one — unless the leftover day falls on a weekend, in which case it drops to 260. The relationship runs the other way: see [how many weekdays are in a year](/blog/how-many-weekdays-in-a-year).

Checking Any Year

Look up January 1. Monday means 53. In a leap year, a Sunday January 1 also means 53, because January 2 is then a Monday.