Holders Russia will travel to Spain for this year's Fed Cup final.
Both sides booked their place in September's team showdown by winning the third rubbers of their semi-finals to establish insurmountable 3-0 leads.
Russia led the USA 2-0 heading into Sunday's reverse singles at the Luzhniki stadium in Moscow and Vera Zvonareva secured the winning point when she came from behind to beat Vania King 4-6 6-3 6-2.
Spain progressed to the final after taking a 3-0 lead against China in Beijing.
Nuria Llagostera Vives beat China's Peng Shuai 6-4 6-4 to book Spain's first appearance in the final since 2002.
Victories by Carla Suarez-Navarro and Llagostera Vives had Spain in a dominant position overnight.
On Saturday, Suarez-Navarro defeated Chinese number one Peng 6-3 7-6, while Llagostera Vives won 6-3 6-4 against Zheng Jie.
Spain went on to win one of the two dead rubers to finish 4-1 winners, while Russia - who will be playing in their fourth Fed Cup final in five years - lost both of theirs to leave the final score in Moscow 3-2.
The final will take place on September 13-14 in Spain, with the hosts likely to choose their favoured clay as the surface.