Days until September 20
September 20 falls on a Sunday in 2026 and a Monday in 2027. The count runs from today’s date on your device to the next September 20; pick another date to count from it instead.
- Days until September 20
- 355
From September 30, 2026, there are 355 days until September 20 on Monday, September 20, 2027.
- Date
- Monday, September 20, 2027
- Day of the week
- Monday
- In weeks
- 50 weeks and 5 days
Answer for the example date Wednesday, September 30, 2026. It changes to today's date when the page loads.
Days until September 20: 355. From September 30, 2026, there are 355 days until September 20 on Monday, September 20, 2027.
Where is September 20 on the calendar?
How to calculate
Counts the days from today, or any date you choose, to the next September 20, with its day of the week.
Example with the default inputs (Count from September 30, 2026) on the example date Wednesday, September 30, 2026: From September 30, 2026, there are 355 days until September 20 on Monday, September 20, 2027.
Method: Find the first September 20 on or after the start date, then count the days from the start date to it.
- September 20 comes every year, so the count is never more than 365 days.
- The start date itself is not counted: from the day before September 20, the count is 1; on September 20 itself, it is 0.
- Start dates from January 1, 1900 to December 31, 2400 work for the count to September 20, the range the date field accepts.
- Today is the date on your own device, so the count to September 20 changes at midnight where you are. Dates are whole calendar days, so a daylight-saving change never adds or loses a day.
Worked examples
Each example is checked against the calculator on every build.
- Count from 2027-09-20 gives Date 2027-09-20, Days until September 20 0.Source: U.S. Naval Observatory, Leap Years: the Gregorian leap year rule (https://aa.usno.navy.mil/faq/leap_years)
- Count from 2027-01-01 gives Date 2027-09-20, Days until September 20 262.Source: U.S. Naval Observatory, Leap Years: the Gregorian leap year rule (https://aa.usno.navy.mil/faq/leap_years)
- Count from 2027-09-21 gives Date 2028-09-20, Days until September 20 365.Source: U.S. Naval Observatory, Leap Years: the Gregorian leap year rule (https://aa.usno.navy.mil/faq/leap_years)
Other questions people ask
What day of the week is September 20?
Sunday, September 20, 2026; Monday, September 20, 2027; Wednesday, September 20, 2028. The weekday of September 20 moves on one day a year, or two when a February 29 falls between.
What day of the year is September 20?
September 20 is day 263 of a common year and day 264 of a leap year, such as 2028. Either way, 102 days of the year come after it.
What season is September 20 in?
In the Northern Hemisphere, September 20 is in summer in every year from 2026 to 2035; in the Southern Hemisphere, it is winter. Seasons here start on the astronomical equinoxes and solstices, dated in US Eastern Time.
Is September 20 a US federal holiday?
No. No US federal holiday falls on September 20. The next one in the calendar after September 20 is Columbus Day, which falls between October 8 and October 14.
How are the days until September 20 counted?
From the start date to September 20, without counting the start date: from September 19 the count is 1, and on September 20 it is 0. The day after, it moves on to the next September 20: from September 21, 2026, that is September 20, 2027, 364 days away.