Rosh HaShanah (Hebrew: רֹאשׁ הַשָּׁנָה, Rōʾš hašŠānā, lit. "start of the year") is the Jewish New Year. The biblical name for this holiday is Yom Teruah (יוֹם תְּרוּעָה, Yōm Tərūʿā), literally "day of shouting or blasting." It is the first of the Jewish High Holy Days (יָמִים נוֹרָאִים, Yāmīm Nōrāʾīm; "Days of Awe"), as specified by Leviticus 23:23–25, that occur in the late summer/early autumn of the Northern Hemisphere. The High Holy Days comprise both Rosh HaShanah and Yom Kippur.

It is the 29th day of the Hebrew month of Elul.

In terms of the Gregorian calendar, the earliest date on which Rosh Hashanah can fall is 5 September, as happened in 1842, 1861, 1899, and 2013. The latest Gregorian date that Rosh Hashanah can occur is 5 October, as happened in 1815, 1929, and 1967, and will happen again in 2043. After 2089, the differences between the Hebrew calendar and the Gregorian calendar will result in Rosh Hashanah falling no earlier than 6 September. Starting in 2214, the new latest date will be 6 October.

In 2020 the Jewish President of Ukraine, Volodymyr Zelenskyy, announced that Ukraine would declare Rosh Hashanah a national holiday.

Rosh Hashana for Hebrew Year 5783 begins at sundown on Sunday, 25 September 2022 and ends at nightfall on Tuesday, 27 September 2022.