Week 21 of 2025 runs May 19, 2025 to May 25, 2025.
Week 21 starts on Monday, May 19, 2025 and ends on Sunday, May 25, 2025. It's the 139th day of the year, sits in Q2, and falls in May. By the end of this week, 145 of 365 days are gone, putting 2025 at 39.7%.
This week includes Victoria Day, so it has 4 working days instead of the usual 5. Need a different week? Browse the full 2025 week calendar, or jump to this week's number.
Week 21 at a glance
The 7 days of week 21
Every date in week 21 of 2025, Monday through Sunday, with day-of-year numbers and events.
| Day | Date | Day no. | Type | Events |
|---|---|---|---|---|
| Monday | Day 139 | Weekday | Victoria Day | |
| Tuesday | Day 140 | Weekday | ||
| Wednesday | Day 141 | Weekday | ||
| Thursday | Day 142 | Weekday | ||
| Friday | Day 143 | Weekday | ||
| Saturday | Day 144 | Weekend | ||
| Sunday | Day 145 | Weekend |
What week 21 of 2025 means
ISO 8601 numbers weeks so every week starts on Monday and ends on Sunday. Week 1 is the one holding the year's first Thursday, which is why early January can land in week 52 or 53 of the previous year. Week 21 is one piece of that system.
In 2025, week 21 covers May 19 – May 25, 2025. That's May, deep in Q2. The same week number shifts by a day or two each year, so week 21 in 2026 won't share these exact dates. The table below shows how it moves.
Want to check a specific date instead of a week number? The week calculator converts any date to its ISO week. Curious how many weeks a year holds? The weeks in a year guide explains 52 versus 53. And the ISO week number page covers the standard end to end.
Holidays in week 21 of 2025
🇨🇦 Canada
Victoria Day
FederalWeek 21 across years
The same ISO week number lands on different dates each year. Here's how week 21 shifts.
Week 21 of 2025: questions and answers
What days are in week 21 of 2025?
Week 21 of 2025 runs from May 19, 2025 (Monday) through May 25, 2025 (Sunday). It spans May.
What month is week 21 in 2025?
Week 21 of 2025 falls entirely in May 2025.
How many working days are in week 21 of 2025?
Week 21 of 2025 has 4 working days — reduced from 5 due to Victoria Day falling on a weekday.
What week is Victoria Day in 2025?
Victoria Day falls in ISO week 21 of 2025 (May 19 – May 25, 2025).
What quarter is week 21 of 2025 in?
Week 21 of 2025 is in Q2 (2025). The week starts on day 139 of 365.
What is ISO week 21?
ISO week 21 is defined by the ISO 8601 international standard. It begins on Monday, May 19, 2025, and ends on Sunday, May 25, 2025. It is week 40% through the ISO year 2025.