When is the spring equinox

when is the spring equinox

When is the spring equinox depends on which hemisphere you call spring. Astronomers name the March equinox and the September equinox. Popular speech in the United States calls the March date the spring or vernal equinox. Popular speech in Australia, New Zealand, Argentina, and South Africa often calls the September date the spring equinox. The Earth does not pick a favorite. Your map does.

The event is a moment, not a whole calendar square. It is the instant the Sun’s center crosses the celestial equator heading north in March, and south in September. In 2026 the March moment is about 14:46 UTC on 20 March. In Eastern Daylight Time that is 10:46 a.m. on the same Friday. In zones well east of UTC the local clock can already be 21 March. Always convert the instant; do not copy the UTC date onto a wall calendar in Auckland without looking.

The March equinox falls on 19, 20, or 21 March depending on the year and the zone. It is not locked to 21 March, even though school posters often print that. 20 March is common. 19 March happens. If a worksheet says “always 21 March,” the worksheet is using a memory, not this year’s almanac.

In 2027 the March equinox is 20 March again, a Saturday, at a later UTC clock time than 2026. The date repeating does not mean the minute repeats.

Equal day and night, almost

The name equinox points at equal night. Daylight and darkness are close to even around that date, everywhere except near the poles, but they are not a perfect 12 hours and 0 minutes on the nose for most towns. The Sun is a disk, not a point, and the atmosphere lifts the apparent Sun at the horizon. Sunrise is a little early and sunset a little late compared with a geometric point-Sun. The day of year when measured daylight is closest to twelve hours can sit a few days off the equinox. That is expected. It is not the equinox “being wrong.”

What is true on the equinox: the Sun rises due east and sets due west for observers who are not at the poles. That direction fact is cleaner than the twelve-hour slogan. If you are checking a compass rose against a sunrise, this is the week to do it, with the usual caution that local horizon hills still win.

March equinox 2026: Friday, 20 March, about 14:46 UTC (northern astronomical spring). September equinox 2026: 23 September (northern astronomical autumn; southern spring). Meteorological northern spring: 1 March through 31 May, a box that does not wait for the moment.

School mnemonic “21 March”: sometimes true, often not; read the year. Spring is a moment in the sky and a mood in the street. Only one of those has a timestamp in UTC.

Season boxes next to the timestamp

Meteorological spring in the north is March, April, and May. That convention exists so climate tables can compare equal months. It starts on 1 March, more than two weeks before the 2026 equinox. Flowers and sports schedules often follow that box, or follow local weather, not the celestial crossing. You can have a warm 5 March and still be waiting for astronomical spring. You can have a snowy 22 March and already be in it.

After the March equinox, northern days continue to lengthen until the June solstice. The equinox is the even-ish crossing, not the longest day. Do not stand outside on 20 March expecting the year’s latest sunset. That prize belongs to a date near the June solstice, and even then the latest sunset and the longest daylight are not always the same square, for the same equation-of-time reasons that split earliest sunset from the December solstice.

Cultures mark the March turning with new-year and light festivals in various calendars. Those dates can sit on the equinox or near it, depending on the tradition and the year. A civil U.S. planner does not close banks for the equinox. The timestamp still happens whether anyone has a day off.