September 2027 has 30 days, running Wednesday, September 1 through Thursday, September 30. It carries one federal holiday, Labor Day on Monday, September 6, and 21 working days.
September 2027 holds the Harvest Moon on Wednesday, September 15 — eight days before the autumn equinox, which is close enough to claim the title under the strict rule that assigns it to the full moon nearest the equinox.
It also produces an unusual same-day pairing: the equinox on Thursday, September 23 at 2:01 a.m. EDT and the last quarter moon four hours later at 6:20 a.m. EDT.
Table of Contents
Holidays in September 2027
| Date | Day | Observance | Type |
|---|---|---|---|
| September 6 | Monday | Labor Day | Federal holiday |
| September 11 | Saturday | Patriot Day, National Day of Service | Commemorative |
| September 15 | Wednesday | National Hispanic Heritage Month begins | Commemorative |
| September 17 | Friday | Constitution Day and Citizenship Day | Commemorative |
| September 19 | Sunday | National POW/MIA Recognition Day | Commemorative |
| September 23 | Thursday | Autumn equinox, 2:01 a.m. EDT | Astronomical |
| September 29 | Wednesday | Michaelmas | Christian |
Labor Day is the only federal holiday in September 2027 (U.S. Office of Personnel Management).
It is fixed to the first Monday in September under 5 U.S.C. 6103, so it always produces a three-day weekend and never requires an observance shift.
The Jewish High Holy Days fall outside September in 2027
This is worth stating because it is unusual. Rosh Hashanah 5788 begins at sundown on Friday, October 1, 2027 and ends at nightfall on Sunday, October 3 (Hebcal). Yom Kippur follows on October 10 to 11.
In most years the High Holy Days fall in September, sometimes spanning into early October.
In 2027 they miss September entirely, because the Hebrew calendar is lunisolar and inserts a leap month in seven years of every nineteen, pushing the Gregorian dates later.
Rosh Hashanah fell on September 11 in 2026 and will fall on September 20 in 2028.
September 2027 calendar closures by institution
| Institution | Monday, September 6, 2027 |
|---|---|
| Federal offices | Closed |
| Banks and Federal Reserve | Closed |
| U.S. Postal Service | No delivery, offices closed |
| NYSE and Nasdaq | Closed |
| Bond markets, SIFMA | Closed |
| State and local government | Closed in all 50 states |
| Public schools | Closed; many districts start the following day |
| Retail and grocery | Open, major sale weekend |
Labor Day is observed uniformly across every state, with no local variation to check.
Events in September 2027
Month-long observances running through all of September 2027:
- National Preparedness Month
- Prostate Cancer Awareness Month
- National Suicide Prevention Awareness Month
- Childhood Cancer Awareness Month
- National Recovery Month
National Hispanic Heritage Month does not run the full calendar month.
It begins on Wednesday, September 15, 2027 and ends on Friday, October 15, spanning the two months rather than sitting inside one.
The September 15 start marks the independence anniversaries of Costa Rica, El Salvador, Guatemala, Honduras and Nicaragua.
Constitution Day on Friday, September 17 commemorates the signing of the Constitution in 1787.
Federal law requires educational institutions receiving federal funds to hold an educational programme on the Constitution that day, which is unusual — it is a mandate on schools rather than a holiday.
September 2027 Events and Observances
September 2027 marks the transition into autumn in the Northern Hemisphere, featuring major civic holidays, Hindu celebrations leading into the festival season, astronomical events, and key international observances.
Check Out National Days in September 2027.
| Date | Day | Event / Observance | Category |
| September 4 | Saturday | Hartalika Teej | Hindu |
| September 4 | Saturday | Ganesh Chaturthi (Vinayaka Chavithi) | Hindu |
| September 6 | Monday | Labor Day | US & Canada Holiday |
| September 8 | Wednesday | International Literacy Day | UN / International |
| September 11 | Saturday | Patriot Day (9/11 Remembrance) | US Commemorative |
| September 12 | Sunday | Grandparents Day | US Observance |
| September 14 | Tuesday | Anant Chaturdashi (Ganesh Visarjan) | Hindu |
| September 15 | Wednesday | Hispanic Heritage Month begins (runs to Oct 15) | Cultural Observance |
| September 16 | Thursday | Mexican Independence Day (Grito de Dolores) | Cultural / National |
| September 16 | Thursday | Pitru Paksha begins (Ancestral homage period) | Hindu |
| September 17 | Friday | Constitution Day and Citizenship Day | US Observance |
| September 21 | Tuesday | International Day of Peace | UN / International |
| September 23 | Thursday | Autumnal Equinox (First Day of Fall) | Astronomical |
| September 27 | Monday | World Tourism Day | UN / International |
| September 30 | Thursday | Sharad Navratri begins | Hindu |
Month Highlights
- Labor Day Weekend (Sept 4–6): The first Monday in September serves as the traditional end-of-summer long weekend and federal holiday in both the US and Canada.
- Hindu Festival Cycle:
- Ganesh Chaturthi begins on September 4, launching a 10-day celebration that concludes with Anant Chaturdashi (idol immersion) on September 14.
- The somber, reflective 16-day period of Pitru Paksha (honoring ancestors) begins September 16 and wraps up just as Sharad Navratri starts on September 30, kicking off the major autumn festival season that leads directly into October’s Dussehra and Diwali.
- Astronomical Equinox (Sept 23): Marks the official start of astronomical autumn in the Northern Hemisphere and spring in the Southern Hemisphere, with nearly equal day and night.
- Jewish Calendar Context: Because 2026–2027 is a regular (non-leap) Jewish year, the High Holy Days land unusually late on the solar calendar; Erev Rosh Hashanah does not occur until sunset on Friday, October 1, leaving September clear of the major Tishrei festivals.
Autumn equinox 2027
The September equinox occurs on Thursday, September 23, 2027 at 2:01 a.m. EDT, which is 06:01 UTC.
It marks the astronomical start of autumn in the Northern Hemisphere and of spring in the Southern.
Astronomical autumn 2027 runs from this equinox to the December solstice on Tuesday, December 21, a span of 89 days and 20 hours — the shortest of the four seasons in the Northern Hemisphere.
Meteorological autumn is defined differently, running September 1 through November 30 as a fixed calendar block.
Day and night are not exactly equal at the equinox. Sunrise and sunset are measured by the Sun’s upper edge rather than its centre, and atmospheric refraction lifts the image of the Sun above the horizon, together adding six to eight minutes of daylight at mid-latitudes.
The date of genuine equality, the equilux, falls a few days after the September equinox.
How many days, weeks and working days in September 2027
September 2027 has 30 days, 4 full weeks plus 2 days, 22 weekdays, and 21 working days after Labor Day is removed.
The calculation:
- September always has 30 days.
- 30 ÷ 7 gives 4 complete weeks with 2 days remaining.
- Eight of the 30 days fall on a Saturday or Sunday, leaving 22 Monday-to-Friday weekdays.
- Labor Day falls on Monday, September 6, a weekday, so 22 − 1 = 21 working days.
September 2027 calendar weekday counts
| Weekday | Occurrences |
|---|---|
| Wednesday | 5 |
| Thursday | 5 |
| Friday | 4 |
| Saturday | 4 |
| Sunday | 4 |
| Monday | 4 |
| Tuesday | 4 |
September 2027 calendar week numbers and day-of-year positions
September 2027 spans ISO weeks 35 through 39. September 1 is day 244 of 2027 and September 30 is day 273, closing the third quarter at 92 days.
September 2027 moon phases
Times are U.S. Eastern Daylight Time. Daylight saving time runs through Sunday, November 7.
| Phase | Date | Time |
|---|---|---|
| First Quarter | Tuesday, September 7 | 2:31 p.m. EDT |
| Full Moon — Harvest Moon | Wednesday, September 15 | 7:03 p.m. EDT |
| Last Quarter | Thursday, September 23 | 6:20 a.m. EDT |
| New Moon | Wednesday, September 29 | 10:35 p.m. EDT |
The Harvest Moon is defined as the full moon nearest the September equinox, not by calendar month. In 2027 the equinox falls on September 23; the September 15 full moon is 8 days before it and the October 15 full moon is 22 days after, so September takes the title and October becomes the Hunter’s Moon.
Almanac sources occasionally differ in years where the gap is narrow. In 2027 it is not narrow, so the assignment is unambiguous.
The last quarter on Thursday, September 23 at 6:20 a.m. EDT falls the same day as the autumn equinox at 2:01 a.m. EDT, four hours and nineteen minutes apart.
Solar and lunar cycles are independent, so this is coincidence rather than pattern.
September 2027 Zodiac, Birthstone and Astrology
September is defined by transitional energy—moving from late summer to the autumn equinox—reflected in its earth-and-air astrological signs, deep-blue gemstone lore, and resilient blooms.
| Attribute | Primary Symbol | Details & Symbolism |
| Zodiac Sign (Early) | Virgo (Aug 23 – Sep 22) | Element: Earth • Ruler: Mercury Practical, analytical, detail-oriented, grounded |
| Zodiac Sign (Late) | Libra (Sep 23 – Oct 22) | Element: Air • Ruler: Venus Diplomatic, harmonious, aesthetic, balanced |
| Primary Birthstone | Sapphire (Corundum) | Represents wisdom, royalty, truth, and protection against negative energy |
| Secondary / Traditional Stones | Lapis Lazuli, Peridot | Ancient and mystical associations with mental clarity and vision |
| Birth Flowers | Aster & Morning Glory | Aster: Wisdom, faith, and patience Morning Glory: Affection, renewal, and resilience |
| Tree Astrology (Celtic) | Vine (Sep 2 – 29) & Ivy (Sep 30+) | Vine represents self-control and equilibrium; Ivy symbolizes determination |
| Element Shift | Earth to Air | Moves from Virgo’s meticulous planning to Libra’s social equilibrium at the Autumn Equinox |
Astrological Breakdown
- Virgo (August 23 – September 22): Marked by the maiden or virgin carrying wheat, representing the harvest. Virgos focus on systems, logic, refinement, and service to others.
- Libra (September 23 – October 22): Begins on the Autumn Equinox, when day and night reach near-equal length. Represented by the scales, Libras prioritize partnership, justice, design, and emotional equilibrium.
Gemstone & Floral Lore
- The Sapphire: Historically associated with nobility and clergy, sapphires were worn to guard against envy and attract divine favor. While sapphires occur in pink, yellow, and green (“fancy sapphires”), royal deep blue remains the classic birthstone shade.
- Asters & Morning Glories: Asters (named from the Greek word for “star”) bloom in late summer and autumn when most other flowers fade. Morning glories unfurl early each day, symbolizing fresh beginnings and adaptability.
Frequently asked questions
How many working days are in September 2027?
21, on a Monday-to-Friday schedule observing Labor Day. The month has 22 weekdays. Labor Day on Monday, September 6 is the only federal holiday subtracted.
When is the autumn equinox 2027?
Thursday, September 23, 2027 at 2:01 a.m. EDT, which is 06:01 UTC. It marks the astronomical start of autumn in the Northern Hemisphere. Meteorological autumn began three weeks earlier, on September 1.
Is the September 2027 full moon the Harvest Moon?
Yes. The Harvest Moon is the full moon nearest the September equinox, and in 2027 that is Wednesday, September 15 at 7:03 p.m. EDT. It falls 8 days before the equinox; the October 15 full moon falls 22 days after, which makes October the Hunter’s Moon.
