Saint Helier (French language: Saint-Hélier, Jèrriais: Saint Hélyi) is one of the twelve parishes of Jersey, the largest of the Channel Islands in the English Channel. St. Helier has a population of about 28,000, roughly 31.2% of the total population of Jersey, and is the capital of the Island (although Government House is situated in St. Saviour). The urban area of the parish of St. Helier makes up most of the largest town in Jersey, although some of the town area is situated in adjacent St. Saviour, with suburbs sprawling into St. Lawrence and St. Clement. The greater part of St. Helier is predominantly rural.

The parish covers a surface area of 4.1 square miles (10.6 km²), being 9% of the total land area of the Island (this includes reclaimed land area of 494 acres (2.00 km²) or 200 ha).

The parish crest is two crossed gold axes on a blue background, symbolising the martyrdom of Helier and the sea.

It is thought that the site of St. Helier was settled at the time of the Roman control of Gaul.

Saint Helier, a 6th century ascetic hermit, is patron saint of Jersey in the Channel Islands, and in particular of the town and parish of Saint Helier, the island’s capital. He is also invoked as a healing saint for diseases of the skin and eyes.

According to hagiography, Hellerius or Helier was born to pagan parents in Tongeren (now in Belgium) after they had had difficulties conceiving a child. In desperation they had turned to Saint Cunibert who had advised them to pray to God and to promise to bring up an eventual child in the Christian faith. Their prayers having been answered, Helier was born, but Helier’s father eventually grew angry at the influence Cunibert exerted over his precocious son, who was already causing consternation with his youthful miracles. Helier’s father had Cunibert killed, whereupon Helier fled.

Helier’s wanderings led him through what is now the village of St. Hellier in the département of Seine-Maritime in Normandy and eventually to the Cotentin where he sought retreat from the distractions of the world in the monastic community of Saint Marculf at Nantus (Nanteuil, now St.-Marcouf-de-l’Isle in Manche).