Week 51 of the year
When is week 51? The exact Monday–Sunday dates of ISO week 51 for every year from 2024 to 2032.
Week 51 of 2026 runs from Monday, Dec 14, 2026 to Sunday, Dec 20, 2026 (December). Week 51 of 2026 is 22 weeks away. ISO week code: 2026-W51.
Week 51 dates by year
| Year | Week 51 starts (Mon) | Week 51 ends (Sun) | Month |
|---|---|---|---|
| 2024 | Monday, December 16, 2024 | Sunday, December 22, 2024 | December |
| 2025 | Monday, December 15, 2025 | Sunday, December 21, 2025 | December |
| 2026 | Monday, December 14, 2026 | Sunday, December 20, 2026 | December |
| 2027 | Monday, December 20, 2027 | Sunday, December 26, 2027 | December |
| 2028 | Monday, December 18, 2028 | Sunday, December 24, 2028 | December |
| 2029 | Monday, December 17, 2029 | Sunday, December 23, 2029 | December |
| 2030 | Monday, December 16, 2030 | Sunday, December 22, 2030 | December |
| 2031 | Monday, December 15, 2031 | Sunday, December 21, 2031 | December |
| 2032 | Monday, December 13, 2032 | Sunday, December 19, 2032 | December |
All weeks
Frequently asked questions
What month is week 51 in?
Week 51 typically falls in December. The exact dates shift by up to a few days from year to year because week 1 is anchored to January 4, not January 1.
How do I write week 51 as a week code?
The ISO code is the year plus W51 — for example 2026-W51, short form 26W51, or YYWW date code 2651. See week number formats.
Are these dates the same in every country?
Yes for ISO 8601 (Monday-start) numbering, which is what this table shows. US Sunday-start calendars can label the same days with a number one higher — see week start conventions.