The story
The company namesake is businessman José Sunsundegui, who founded the company in the Basque Country town of Irún in 1944. Sunsundegui initially started out as a rolling stock repair workshop for Renfe, the Spanish state railway company. This practice continued until the 1980s, when Renfe began to open their own engineering workshops and ceased to use Sunsundegui's services; the company changed focus as a result, launching their first production coach, the Sunsundegui Korinto, in 1987. In 2017, Sunsundegui moved into a €5.5 million new factory in Alsasua.
The first model to see significant export success was the Sunsundegui Sideral, which was exported to the United Kingdom and the Republic of Ireland in large numbers in the early to mid-2000s. In the late 2010s and early 2020s, the Sunsundegui SB3 and SC5 were ordered in large numbers by Bus Éireann, Go-Ahead Ireland and Ulsterbus for intercity bus services on the island of Ireland; Israel also emerged as another strong export market for the company. Translink Ulsterbus ordered 30 tri-axle Sunsundegui SC5-bodied Volvo B11R coaches for intercity routes in September 2019, followed by a further 30 identical vehicles in September 2020 for Goldline services.
Sunsundegui produced 462 buses and coaches in 2019; by 2022, exports to other countries made up 86% of Sunsundegui's total production. Sunsundegui received a loan of €8.9 million from the provincial government of Navarre in May 2022, after struggling through the COVID-19 pandemic due to a reduced demand for new vehicles. Prior to the pandemic, Sunsundegui employed 550 people; this reduced to 250 employees by March 2022, although plans were in place to begin new recruitments. After being granted the loan, Sunsundegui announced their intention to commence construction of electric vehicles from 2024. In 2025, the company went into liquidation.
From Wikipedia’s article on Sunsundegui, shared under CC BY-SA 4.0.4