Born in Logroño, La Rioja, but nonetheless a product of Athletic Bilbao's famed youth academy at Lezama, Aranzubia made his first-team debut on 10 June 2001 in a 1–3 home derby loss against Real Sociedad.

[4] On 13 July 2008, Aranzubia joined Deportivo de La Coruña on a three-year deal,[5] helping the Galicians to the UEFA Intertoto Cup and starting throughout the entire season, save one match due to suspension.

[10] He made his debut in the UEFA Champions League on 11 December 2013 shortly after his 34th birthday, saving a penalty from FC Porto's Josué in a 2–0 group stage home victory.

[11] As the Belgian was unavailable due to injury, Aranzubia first played in the league with the Colchoneros on 8 February 2014, being sent off in the last minutes of a 0–2 loss at Almería after fouling Jonathan Zongo in the box.

[14] Previously, Aranzubia helped the nation win the 1999 FIFA World Youth Championship and finish runner-up at the 2000 Summer Olympics, starting in both finals.