Week 49, 2027
December 6–12, 2027
Monday December 6 – Sunday December 122027-W49Days 340–346
The seven days
| Date | ISO week date | Day of year | US week | Islamic date (computed) | Holidays and other dates |
|---|---|---|---|---|---|
| Mon, Dec 6 | 2027-W49-1 | 340 | 50 | 8 Rajab 1449 AH | Constitution Day (Spain) |
| Tue, Dec 7 | 2027-W49-2 | 341 | 50 | 9 Rajab 1449 AH | |
| Wed, Dec 8 | 2027-W49-3 | 342 | 50 | 10 Rajab 1449 AH | Immaculate Conception (Spain) |
| Thu, Dec 9 | 2027-W49-4 | 343 | 50 | 11 Rajab 1449 AH | |
| Fri, Dec 10 | 2027-W49-5 | 344 | 50 | 12 Rajab 1449 AH | |
| Sat, Dec 11 | 2027-W49-6 | 345 | 50 | 13 Rajab 1449 AH | |
| Sun, Dec 12 | 2027-W49-7 | 346 | 51 | 14 Rajab 1449 AH |
About week 49
In US numbering, where weeks start on Sunday and the week of January 1 is week 1, Monday to Saturday are US week 50 and Sunday US week 51.
Holidays this week: Constitution Day on Mon, Dec 6 in Spain; Immaculate Conception on Wed, Dec 8 in Spain. All weeks of 2027 lists the neighbouring weeks.
Week 49 in other years
| Year | Week 49 runs |
|---|---|
| 2025 | Mon, Dec 1 – Sun, Dec 7 |
| 2026 | Mon, Nov 30 – Sun, Dec 6 |
| 2027 | Mon, Dec 6 – Sun, Dec 12 |
| 2028 | Mon, Dec 4 – Sun, Dec 10 |
| 2029 | Mon, Dec 3 – Sun, Dec 9 |
| 2030 | Mon, Dec 2 – Sun, Dec 8 |
In 2028, week 49 runs Mon, Dec 4 – Sun, Dec 10: 364 days later, 2 days earlier in the calendar. Over the 400-year cycle, the Monday of week 49 falls between November 29 and December 6.
By the end of week 49, 346 days of 2027 have passed (94.8% of the year), and 3 ISO weeks of 2027 remain. The week falls in Q4.
Writing week 49
ISO 8601 writes this week as 2027-W49 (basic format 2027W49), from 2027-W49-1 on Monday to -7 on Sunday. The week number page shows the spreadsheet and Python formulas that give these numbers.