Days until September 18
September 18 falls on a Friday in 2026 and a Saturday in 2027. The count runs from today’s date on your device to the next September 18; pick another date to count from it instead.
- Days until September 18
- 353
From September 30, 2026, there are 353 days until September 18 on Saturday, September 18, 2027.
- Date
- Saturday, September 18, 2027
- Day of the week
- Saturday
- In weeks
- 50 weeks and 3 days
Answer for the example date Wednesday, September 30, 2026. It changes to today's date when the page loads.
Days until September 18: 353. From September 30, 2026, there are 353 days until September 18 on Saturday, September 18, 2027.
Where is September 18 on the calendar?
How to calculate
Counts the days from today, or any date you choose, to the next September 18, 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 353 days until September 18 on Saturday, September 18, 2027.
Method: Find the first September 18 on or after the start date, then count the days from the start date to it.
- September 18 comes every year, so the count is never more than 365 days.
- The start date itself is not counted: from the day before September 18, the count is 1; on September 18 itself, it is 0.
- Start dates from January 1, 1900 to December 31, 2400 work for the count to September 18, the range the date field accepts.
- Today is the date on your own device, so the count to September 18 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 2027-09-18 gives Date 2027-09-18, Days until September 18 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 2027-09-18, Days until September 18 260.Source: U.S. Naval Observatory, Leap Years: the Gregorian leap year rule (https://aa.usno.navy.mil/faq/leap_years)
- Count from 2027-09-19 gives Date 2028-09-18, Days until September 18 365.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 18?
Friday, September 18, 2026; Saturday, September 18, 2027; Monday, September 18, 2028. The weekday of September 18 moves on one day a year, or two when a February 29 falls between.
What day of the year is September 18?
September 18 is day 261 of a common year and day 262 of a leap year, such as 2028. Either way, 104 days of the year come after it.
What season is September 18 in?
In the Northern Hemisphere, September 18 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 18 a US federal holiday?
No. No US federal holiday falls on September 18. The next one in the calendar after September 18 is Columbus Day, which falls between October 8 and October 14.
How are the days until September 18 counted?
From the start date to September 18, without counting the start date: from September 17 the count is 1, and on September 18 it is 0. The day after, it moves on to the next September 18: from September 19, 2026, that is September 18, 2027, 364 days away.