Šaca (Hungarian: Saca) is a borough (city ward) of Košice, Slovakia. Located in the Košice II district, at an altitude of roughly 244 metres (801 ft) above sea level, it is home to several important hospitals and medical facilities, as well as Košice's steel works and other heavy industry. One of Šaca's localities is Bužinka, which includes some of the borough's older historical architecture.

The first written record about Šaca dates back to 1275. Since 1427 the landowners of Šaca were the Semsey family, who built a castle here in the 15th century. It was demolished later in the same century, on the order of the King Matthias Corvinus. Later members of the family built a rococo manor house in Šaca in the late 18th century, which stands to this day. Water mills were operated in Šaca since the Middle Ages, until 1950.

After World War II, the village became a residential district for builders of a new steelworks company - Východoslovenské železiarne Košice (VSŽ Košice - "East Slovak Ironworks, Košice"). In January 1960 construction started on more than 8 square kilometres of land. In 1965 the first blast furnace was fired up and production in the hot rolling mill and coke plant was started. In four decades the Košice mill has developed into a steel-producing plant that has managed to reach the markets and achieve a position among the significant steel producers. It has been accepted as a member of prestigious international organizations associating iron and steel producers and has become a partner of renowned foreign firms in joint ventures. The new phase in the history of the factory started on November 24, 2000 when the metallurgy production and commercial activities were sold to the United States Steel Corporation and VSŽ Košice changed its name to U. S. Steel Košice.

In the 1970s, Šaca gained an urban character and became one of 22 boroughs of Košice.

Some of the historical names of Šaca.

• 1275 - Latin: Ida
• 1280 - terra Eghazas Ida
• 1319 - poss. Saticha
• 1328 - poss. Zethyce alio nomine Scenthtrinitas
• 1344 - Setyche
• 1372 - poss. Setyche
• 1379 - poss. Sathicha, poss. Satycha
• 1385 - Sathicha, poss. Sathycha alio nomine Screben
• 1393 - Sathicha, Sagcza al. Nom. Zenthtrinitas
• 1395 - poss. Seu villa Senthythe
• 1409 - poss. Sethithe, poss. Sethyche
• 1424 - villa Saczcza
• 1427 - poss. Sechcha, Secha
• 1428 - poss. Sathcza
• 1469 - poss. Sacza
• 1471 - poss. Saccza
• 1474 - poss. Saczcza
• 1477 - poss. Saczcza
• 1514 - Saccza
• 1553 - Sacha
• 1773 - Hungarian: Szácza
• 1786 - Sacza
• 1808 - Slovak: Ssáca, Hungarian: Sácza
• 1863 - Saca
• 1903 - sk: Šaca, hu: Sacza
• 1906, 1938 - sk: Šaca, hu: Saca

A 1770s Roman Catholic church in the Bužinka locality.

A rococo manor house of the Semsey family, built in the 1770s (in preserved condition), and a smaller manor house in the Bužinka locality (currently ruined).

• Area: 41.2 square kilometres (15.9 sq mi)
• Population: 5,890 (31 December 2017)
• Density of population: 140/km (31 December 2017)
• District: Košice II
• Mayor: Daniel Petrík (as of 2018 elections)

There are several sports facilities in the Šaca borough, including a football (soccer) stadium.

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  Soccer stadium at the sports area in Šaca
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  Park with playground in Šaca

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  The Assumption of the Virgin Mary Church, a Roman Catholic parish church, initially The Holy Trinity Church (erected in 1779)
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  The Assumption of the Virgin Mary Church, a Roman Catholic parish church, initially The Holy Trinity Church (erected in 1779)
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  Old manor house in Šaca's Bužinka locality
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  Rococo manor house of the Semsey family in Šaca (erected in 1776)
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  Hospital in Šaca
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  U. S. Steel Košice, s.r.o.

• Official website of the Šaca borough
• Article on the Šaca borough at Cassovia.sk
• Official website of U. S. Steel Košice
• Official website of Košice