Week 1 in 2026

WEEK
1

This week starts on Sunday, December 28, 2025 and ends on Saturday, January 3, 2026.

WEEK EUROPE & ISO
1

This week starts on Monday, December 29, 2025 and ends on Sunday, January 4, 2026.

Week 1 of 2026 spans the turn of the year: it begins on December 29, 2025 and ends on January 4, 2026.

Weeks since this week: 41

Week 1 of 2026 at a glance

Starts (Monday)December 29, 2025
Ends (Sunday)January 4, 2026
US week (Sunday to Saturday)1 (December 28, 2025)
MonthDecember / January
QuarterQ1
Year completed at the end of this week1.1%
Weeks left in 2026 after this week52
Weeks in 202653
Even or odd weekOdd

All days in Week 1:

  • Monday, December 29, 2025
  • Tuesday, December 30, 2025
  • Wednesday, December 31, 2025
  • Thursday, January 1, 2026
  • Friday, January 2, 2026
  • Saturday, January 3, 2026
  • Sunday, January 4, 2026

Calendar for December 2026

December 2026
SuMoTuWeThFrSa
Week 4912345
Week 506789101112
Week 5113141516171819
Week 5220212223242526
Week 12728293031
USA Calendar

All Weeks in 2026:

Past & Future Week 1:

US and ISO week numbers

In the US system, where weeks start on Sunday and week 1 is the week that contains 1 January, this is week 1 of 2026. It runs from December 28, 2025 to January 3, 2026.

Even and odd weeks

Week 1 is an odd week. Even and odd week numbers are used for alternating schedules such as shift rotas, school timetables, custody arrangements and waste collection.

Week 1 in other years

FromTo
Week 1 in 2024January 1, 2024January 7, 2024
Week 1 in 2025December 30, 2024January 5, 2025
Week 1 in 2027January 4, 2027January 10, 2027
Week 1 in 2028January 3, 2028January 9, 2028

How week numbers are counted

Most of the world numbers weeks according to the ISO 8601 standard. A week starts on Monday, and week 1 is the week that contains the first Thursday of the year, which is always the week that contains 4 January.

Week 1 of 2026 began on December 29, 2025. 2026 has 53 ISO weeks, because 1 January 2026 falls on a Thursday.

Because of this rule, the first days of January can belong to the last week of the previous year, and the last days of December can belong to week 1 of the next year.

In the United States, weeks usually start on Sunday and week 1 is the week that contains 1 January, so the US week number can differ from the ISO week number.

Find the week number of a date

Frequently Asked Questions (FAQ)

When does week 1 of 2026 start and end?

Week 1 of 2026 starts on December 29, 2025 and ends on January 4, 2026 (ISO 8601, Monday to Sunday).

Which month is week 1 of 2026 in?

Week 1 of 2026 starts in December and ends in January.

What dates are in week 1 of 2026?

December 29, 2025, December 30, 2025, December 31, 2025, January 1, 2026, January 2, 2026, January 3, 2026, and January 4, 2026

How many weeks does 2026 have?

2026 has 53 ISO weeks, because 1 January 2026 falls on a Thursday.

Is week 1 an even or odd week?

Week 1 is an odd week.

What is the US week number for this week?

In the US system, where weeks start on Sunday and week 1 is the week that contains 1 January, this is week 1 of 2026. It runs from December 28, 2025 to January 3, 2026.

Overview of Week 1

Week 1 of the year marks a fresh start, filled with new beginnings and opportunities. It's a time when people reflect on the past year and set resolutions for the year ahead. This week is often characterized by a mix of excitement and determination as individuals aim to kick off the year on a positive note. Notable events, such as New Year's Day, set the tone for the week, making it a significant period for many.

Summary of Week 1

Week 1 typically includes:

  • New Year's Day (January 1st)
  • Common themes: Resolutions, fresh starts, goal setting
  • Activities: Celebrations, planning, reflecting
  • Approach: Optimistic, motivated, reflective

Major Themes of Week 1

Week 1 is often centered around new beginnings. People use this time to set goals, make resolutions, and plan for the year ahead. The theme of renewal is prevalent, with many taking the opportunity to start fresh in various aspects of their lives, such as health, career, and personal growth.

Significant Historical Events and Observances

One of the most significant events during Week 1 is New Year's Day, celebrated on January 1st. This day is marked by various traditions and customs worldwide. For example:

  • New Year’s Resolutions: A tradition where individuals set goals for the coming year.
  • Fireworks: Many countries celebrate with grand fireworks displays.
  • Parades: Events like the Rose Parade in Pasadena, California, are popular.

Additionally, some cultures observe other significant days during this week:

  • Japan: Shogatsu (New Year) is celebrated with family gatherings and traditional foods.
  • Scotland: Hogmanay, a New Year’s Eve celebration, includes customs like first-footing.

Interesting Facts and Cultural Insights

Week 1 is rich with interesting facts and cultural practices:

  • Approximately 45% of Americans make New Year’s resolutions, though only about 8% achieve them.
  • The tradition of making resolutions dates back to ancient Babylon, where people made promises to their gods at the start of each year.
  • In Spain, it’s customary to eat 12 grapes at midnight on New Year’s Eve, one for each stroke of the clock, to bring good luck for the 12 months ahead.

Activities and Practices for Week 1

Engaging in certain activities during Week 1 can set a positive tone for the rest of the year. Here are some suggestions:

  1. Set Realistic Goals: Take time to reflect on the past year and set achievable goals for the new year. This can include personal, professional, and health-related objectives.
  2. Declutter and Organize: Start the year with a clean slate by decluttering your living space and organizing your belongings.
  3. Practice Gratitude: Reflect on what you’re grateful for from the past year and express gratitude to those who made a positive impact on your life.
  4. Plan Ahead: Use a planner or digital calendar to map out important dates and deadlines for the year ahead.
  5. Connect with Loved Ones: Reach out to family and friends to share your hopes and plans for the new year, strengthening your relationships.

These activities not only help in setting a productive and positive tone for the year but also contribute to personal growth and well-being.