He began his career in Iceland with Valur and ÍBV before moving to England where, after an initial loan spell with Torquay United, he joined Brentford, making over 100 appearances.

He moved to Reading in 2003, spending the next eight years with club and amassing 281 appearances before ending his career with a short spell at Ipswich Town.

[6] Rumours were rife that a deal had already been done to take Ívar elsewhere at the end of his loan spell, and, after four league games for the Gulls, he duly signed for Brentford in November 1999 for £150,000,[7] confirming the fears of Torquay fans that he would never be a permanent fixture at Plainmoor.

[citation needed] While at Brentford, the band The Bluetones named one of their instrumental B-sides Ingimarsson in his honour; Adam Devlin, the guitarist, being a Bees fan.

He signed for Wolverhampton Wanderers the following month,[9] but was unable to establish himself at Molineux,[citation needed] resulting in a loan spell with Brighton & Hove Albion in February 2003.

[15] Ívar played in all of Reading's FA Cup matches in the 2009/10 campaign including their famous 2–1 win over Liverpool at Anfield.

[18] Following a disappointing first half to the 2011–12 season, after six starts and two substitute appearances, on 7 January 2012 it was announced that Ívar's contract had been terminated by mutual consent.

He opted to retire from international football for a period of just under two years because of arguments with the former joint-managers Ásgeir Sigurvinsson and Logi Ólafsson.