Halberstam
Halberstam (‎, ‎) is a Jewish surname, used by several branches of the Halberstadt family.

Halberstam, meaningless in its current form, is altered from an older name, Halberstadt, used by many descendants of Rabbi Tzvi Hirsh (died 1748), the rabbi of Halberstadt.

The change of Halberstadt to Halberstam is often thought to have been implemented by Rabbi Chaim Halberstam of Sanz (Nowy Sącz), as implied by Rabbi Yechezkel Michelsohn of Płońsk, in his biography of Rabbi Tzvi Hirsh Halberstadt and his descendants, who records the rabbi of Sanz's displeasure at bearing the name of a non-Jewish settlement as his motive. However, even first and second cousins of the rabbi of Sanz are known to have borne the modified name, implying that the change was made at least two generations before him. Joseph Kwadrat believes that Halberstadt was modified to Halberstam (or, in one branch, to Halberthal) by members of the family then residing in Galicia to conform with the surname adoption laws of the Austrian Empire.

Notable people with surname
Ari Halberstam (1977–1994), Yeshiva student killed in the 1994 Brooklyn Bridge shooting
Ben Zion Halberstam (1874–1941), Grand Rebbe of Bobov (1905–1941)
Ben Zion Aryeh Leibish Halberstam (born 1954), Bobover Rebbe
Chaim Halberstam (1793–1876), of Sanz, founder of the Sanz dynasty. Known commonly as the Divrei Chaim
Chaim Halberstam, descendant of the 'Divrei Chaim' of Sanz, Congregational Rabbi and clinical psychologist
David Halberstam (1934–2007), American journalist and author
David J. Halberstam, American sports announcer
Devorah Halberstam, American anti-terrorism and gun control activist
Dovid Halberstam (1821-1894), founder of the Chrzanow Hasidic dynasty 
Heini Halberstam (1926–2014), mathematician, Elliott–Halberstam conjecture is named
Judith Halberstam, Professor of English and Director of The Center for Feminist Research at University of Southern California
Michael J. Halberstam (1932–1980), American cardiologist and author
Moshe Halberstam (1932–2006), member of the Edah Charedis Rabbinical court of Jerusalem
Naftali Halberstam (1931–2005), Grand Rebbe of Bobov (2000–2005)
Samuel David Halberstam, Klausenberg Rebbe of Borough Park, Brooklyn
Shlomo Halberstam (first Bobover rebbe) (1847–1905), founder of the Bobov Hasidic dynasty
Shlomo Halberstam (third Bobover rebbe) (1907–2000), Grand Rebbe of Bobov (1941–2000)
Solomon Joachim Halberstam, Austrian Jewish scholar
Yechezkel Shraga Halberstam (1813–1899)
Yekusiel Yehudah Halberstam (1905–1994), Orthodox rabbi and founding rebbe of the Klausenberger dynasty
Zvi Elimelech Halberstam, Klausenberg Rebbe of Netanya