The pair played in all the weekend's matches but fatigue was not a factor for the effervescent 33-year-old Stepanek, ranked 37th in the world, who used all his experience to unnerve the 11th-ranked Almagro in the Spaniard's first final appearance.
Stepanek, who became the first man aged 30 or above to win a decisive fifth rubber in 100 years and has plans to play Davis Cup again next year, broke Almagro to claim the first set.
After missing a few chances to break his opponent at the end of the second set, Stepanek managed to force Almagro into several errors in the tiebreak which he won 7-0.
The beginning of the third set was tight but Almagro served well and managed to win it before Stepanek clinched the fourth to send the Czech fans into raptures as Queen's "We are the Champions" blared through the loudspeakers.
Image: Wife of Radek Stepanek Nicole Viadisova, right, and girlfriend of Tomas Berdych Ester Satorova, left, cheer for the Czech Republic during the Davis Cup finals against Spain in Prague, Czech Republic, Sunday, Nov. 18, 2012. Czech Republic defeated Spain 3-2 and gained the Davis Cup trophy.