|Born||27 March 1974 (age 44)|
|Highest ranking||66 (2003/2004)|
(1999 British Open qualifying)
|Best ranking finish||Last 32 (x3)|
Born in 1974, Helgason turned professional in 1995. In 1998, he reached the last 48 at the Irish Open, losing 3–5 to Billy Snaddon, but made no further progress in any tournament that season.
The following season, he reached the last 32 at the 2000 Scottish Open, where he defeated Nick Pearce, John Read and Jamie Burnett before losing 3–5 to Mark Williams. In that year's World Championship, he beat Joe Jogia, John Lardner, Joe Johnson, Rod Lawler and Terry Murphy to set up a meeting in the first round at the Crucible Theatre with Stephen Lee. Becoming the first Icelander to appear at the Crucible, Helgason lost 3–10.
In the last 48 at the 2002 China Open, Helgason faced Anthony Hamilton, building a 4–0 lead with consecutive breaks of 93, 91 and 83; however, Hamilton won the next five frames to run out a 5–4 victor.
Helgason played at the last 32 stage of a ranking event for the third time at the 2002 British Open; there, he defeated Jin Long, Ryan Day, Stuart Bingham, Patrick Wallace and Dave Harold, but lost 3–5 to Paul Hunter.
Having reached a career-high ranking of 66th for the 2003/2004 season, Helgason played in only the first two tournaments, losing in the LG Cup 4–5 to Ian Brumby and in the British Open, 4–5 to Michael Wild. He finished the season ranked 103rd, and lost his professional status at the age of 30.
Amateur finals: 13 (9 titles, 4 runners-up)
|Outcome||No.||Year||Championship||Opponent in the final||Score|
|Winner||1.||1993||World Under-21 Amateur Championship||Indika Dodangoda||11–7|
|Winner||2.||1994||Iceland Amateur Championship||Gunnar Valsson||9–4|
|Winner||3.||1996||Iceland Amateur Championship||Johannes Johannesson||9–6|
|Runner-up||1.||1996||European Amateur Championships||Graham Horne||5–8|
|Winner||4.||1997||Iceland Amateur Championship||Johannes Johannesson||9–5|
|Runner-up||2.||1997||European Amateur Championships||Robin Hull||3–7|
|Runner-up||3.||1998||Iceland Amateur Championship||Johannes Johannesson||5–9|
|Winner||5.||1998||European Amateur Championships||Alex Borg||7–2|
|Runner-up||4.||2005||European Amateur Championships||Alex Borg||2–7|
|Winner||6.||2012||Iceland Amateur Championship||Thorri Jensson||9–1|
|Winner||7.||2017||Nordic Snooker Championship||Patrik Tiihonen||5–2|
|Winner||8.||2017||Iceland Amateur Championship||Jon Ingi Ægisson||9–0|
|Winner||9.||2017||European 6-Reds Championship||Wayne Brown||5–2|
- Kristjan Helgason at CueTracker.net: Snooker Results and Statistic Database