Week 1, 2026
ISO-8601 Standard Week
Week 1 of 2026 runs from December 29, 2025 to January 4, 2026, and 2026 has 53 weeks in total.
This week is already in the past. See the full 2026 calendar, or learn why some years have 53 weeks.
Starts On
Monday
December 29, 2025
Ends On
Sunday
January 04, 2026
This week marks approximately 99% of the year 2026 passed.
December 2026 Calendar
| Week | Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|---|
| 49 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| 50 | 8 | 9 | 10 | 11 | 12 | 13 | 14 |
| 51 | 15 | 16 | 17 | 18 | 19 | 20 | 21 |
| 52 | 22 | 23 | 24 | 25 | 26 | 27 | 28 |
| 1 | 29 | 30 | 31 | 1 | 2 | 3 | 4 |
Holidays in Week 1
Public Holidays Around the World in Week 1, 2026
- Thu, Jan 01 New Year's Day United States
All Weeks in 2026
Week 1 in Other Years
Compare dates and holidays for week 1 across different years:
About Week 1
Week 1 of 2026 is a standard business week consisting of 7 days. It follows the ISO-8601 convention where Monday is the first day of the week.
Working Days
In most countries, this week contains 5 working days (Monday, December 29 to Friday, January 02) and a standard 2-day weekend.