E.ON IT Slovakia spol. s r.o. was founded in 2003 in pursuance of the international expansion strategy of E.ON IS GmbH, the IT service provider of the E.ON utility companies. In the aforementioned year, the companies were acting on the market under the names is:energy GmbH and is:energy slovakia spol. s r.o.

1994	foundation of GEDOS GmbH as IT service provider of the Bayernwerk group in Southern Germany
1999	foundation of Synergis GmbH as the IT provider of PreussenElektra in Northern Germany – a joint venture of PreussenElektra and Cap Gemini Ernst & Young
2001	with merger of Bayernwerk and PreussenElektra into E.ON Energie AG, their IT service providers GEDOS and synergis merge to create is:energy GmbH, the partners of the new company are E.ON Energie and Cap Gemini Ernst& Young
2003	foundation of is:energy slovakia spol. s r.o. a joint venture of is:energy GmbH (51%) and Západoslovenská energetika a.s. (49%)
2005	after changes in ownership structure, is:energy GmbH becomes a 100% E.ON company, and changes its name to E.ON IS GmbH. Subsequently, starting 1 April, 2005, is:energy slovakia start to present itself on the market as E.ON IS Slovakia spol. s r.o., and becomes part of the largest power-engineering group, E.ON.
2010	as a reaction to changes within the E.ON Group, the structure and activity organisation of E.ON IS Group change as well. In a result, the E.ON IS Group changes its name and, starting 1 April, 2010, the group, including all its subsidiaries, starts to present itself as E.ON IT. E.ON IS Slovakia therefore changes on 1st April 2010 its name to E.ON IT Slovakia spol. s r.o. and uses exclusively the E.ON logo.