Week 40 in 2026

WEEK
40

This week starts on Sunday, September 27, 2026 and ends on Saturday, October 3, 2026.

WEEK EUROPE & ISO
40

This week starts on Monday, September 28, 2026 and ends on Sunday, October 4, 2026.

Week 40 of 2026 begins on September 28, 2026 and ends on October 4, 2026. It covers days 271 to 277 of the year and falls in quarter 3.

This is the current week.

Week 40 of 2026 at a glance

Starts (Monday)September 28, 2026
Ends (Sunday)October 4, 2026
US week (Sunday to Saturday)40 (September 27, 2026)
MonthSeptember / October
QuarterQ3
Days of the year271–277
Year completed at the end of this week75.9%
Weeks left in 2026 after this week13
Weeks in 202653
Even or odd weekEven

All days in Week 40:

  • Monday, September 28, 2026
  • Tuesday, September 29, 2026
  • Wednesday, September 30, 2026
  • Thursday, October 1, 2026
  • Friday, October 2, 2026
  • Saturday, October 3, 2026
  • Sunday, October 4, 2026

Calendar for September 2026

September 2026
SuMoTuWeThFrSa
Week 3612345
Week 376789101112
Week 3813141516171819
Week 3920212223242526
Week 4027282930
USA Calendar

All Weeks in 2026:

Past & Future Week 40:

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 40 of 2026. It runs from September 27, 2026 to October 3, 2026.

Even and odd weeks

Week 40 is an even week. Even and odd week numbers are used for alternating schedules such as shift rotas, school timetables, custody arrangements and waste collection.

Week 40 in other years

FromTo
Week 40 in 2024September 30, 2024October 6, 2024
Week 40 in 2025September 29, 2025October 5, 2025
Week 40 in 2027October 4, 2027October 10, 2027
Week 40 in 2028October 2, 2028October 8, 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 40 of 2026 start and end?

Week 40 of 2026 starts on September 28, 2026 and ends on October 4, 2026 (ISO 8601, Monday to Sunday).

Which month is week 40 of 2026 in?

Week 40 of 2026 starts in September and ends in October.

What dates are in week 40 of 2026?

September 28, 2026, September 29, 2026, September 30, 2026, October 1, 2026, October 2, 2026, October 3, 2026, and October 4, 2026

How many weeks does 2026 have?

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

Is week 40 an even or odd week?

Week 40 is an even 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 40 of 2026. It runs from September 27, 2026 to October 3, 2026.

Week 40: An Overview

Week 40 of the year holds a unique position as it typically falls in early October. This week often marks the transition from late summer to early autumn in the Northern Hemisphere, bringing with it a change in weather, scenery, and activities. It is a time when people start preparing for the colder months ahead, and various cultural, historical, and social events take place. Let’s delve into the significance of Week 40 and what makes it special.

Summary of Week 40

Week 40 generally spans from October 1st to October 7th. During this week, several notable events and observances occur, such as World Teachers' Day and the Feast of St. Francis of Assisi. Common themes include the celebration of education, the environment, and the harvest season. People often engage in activities like apple picking, attending fall festivals, and preparing their homes for winter.

Major Themes of Week 40

Week 40 is rich with themes that reflect the changing season and various cultural observances. Here are some of the major themes associated with this week:

Education and Appreciation

World Teachers' Day, celebrated on October 5th, is a significant event during Week 40. This day honors teachers and their contributions to education and society. Schools and communities often organize events to show appreciation for educators, highlighting the importance of education and lifelong learning.

Environmental Awareness

The Feast of St. Francis of Assisi, observed on October 4th, is another key event. St. Francis is known for his love of nature and animals, making this day a time to reflect on environmental stewardship and the importance of caring for our planet. Many people participate in activities like planting trees, cleaning up local parks, and promoting sustainable practices.

Harvest Celebrations

As autumn progresses, Week 40 is also a time for harvest celebrations. In many regions, this week coincides with the peak of the apple harvest season. Families and communities come together for apple picking, cider making, and enjoying the bounty of the season. Fall festivals featuring local produce, crafts, and entertainment are common during this time.

Historical Events and Observances

Several significant historical events and observances fall within Week 40. Here are a few notable ones:

World Teachers' Day (October 5th)

Established in 1994 by UNESCO, World Teachers' Day celebrates the vital role teachers play in providing quality education. It is an opportunity to acknowledge their hard work and dedication, as well as to address challenges faced by educators worldwide.

Feast of St. Francis of Assisi (October 4th)

This religious observance honors St. Francis of Assisi, the patron saint of animals and the environment. Many churches hold special services and blessings for pets, and environmental organizations use this day to promote conservation efforts.

National Poetry Day (UK) (First Thursday of October)

In the United Kingdom, National Poetry Day is celebrated on the first Thursday of October. This day encourages people to read, write, and share poetry, fostering a love for the literary arts and creative expression.

Interesting Facts and Cultural Insights

Week 40 offers a wealth of interesting facts and cultural insights. Here are a few to consider:

  • Changing Leaves: In many parts of the Northern Hemisphere, Week 40 marks the beginning of the peak fall foliage season. The vibrant colors of the changing leaves attract tourists and nature enthusiasts alike.
  • Harvest Moon: The full moon closest to the autumnal equinox is known as the Harvest Moon. It often occurs around Week 40 and provides extra light for farmers to work late into the night during the harvest season.
  • Oktoberfest: Although it officially starts in late September, Oktoberfest celebrations often continue into Week 40. This famous German festival features beer, traditional foods, music, and dancing.

Activities and Practices for Week 40

There are plenty of activities and practices that people can engage in during Week 40. Here are some suggestions:

Celebrate World Teachers' Day

  • Write a thank-you note to a teacher who has made a difference in your life.
  • Participate in or organize a community event to honor local educators.
  • Donate books or supplies to a school in need.

Embrace Environmental Stewardship

  • Plant a tree or start a garden to contribute to a greener planet.
  • Join a local cleanup effort to help maintain parks and natural areas.
  • Reduce your carbon footprint by biking or walking instead of driving.

Enjoy Harvest Activities

  • Visit a local orchard for apple picking and enjoy fresh, seasonal produce.
  • Attend a fall festival to experience the sights, sounds, and flavors of the season.
  • Try your hand at making homemade apple cider or baking an apple pie.

Engage with Poetry

  • Read a poem each day to appreciate the beauty of language and expression.
  • Write your own poems and share them with friends or family.
  • Attend a poetry reading or open mic night to support local poets.

Week 40 is a time of transition and celebration, offering a variety of ways to engage with the world around us. Whether you are honoring teachers, caring for the environment, or enjoying the harvest season, there is something for everyone to appreciate during this special week.