Having spent most of his career playing for Breiðablik, he has also had stints abroad for AEK Athens, Stabæk, Randers FC and AC Horsens.
[2] His second appearance made against Anderlecht in the Europa League on 1 December 2011, but he never had an opportunity in a Superleague Greece match.
On 31 January 2013, Elfar signed a new short-term contract, this time with Randers FC from Denmark for the spring season of 2013.
[4] On 6 January 2017, it was confirmed, that AC Horsens had signed Helgason on a loan deal for the rest of the season with a buying option.
In May 2017 in an interview after scoring in a game against Odense Boldklub Helgason revealed, that he suffered from homesickness and wanted to return to Iceland.