The Pole and the American beat the duo of Romanian Irina-Camelia Begu and Argentina's Nadia Podoroska 6-3, 6-4 in their semi-final match on Friday.
Świątek and Mattek-Sands, the No. 14 seeds, make their bid for the championship title on Sunday.
They will take on second-seeded Czechs Barbora Krejčíková and Kateřina Siniaková, who defeated Poland's Magda Linette and America's Bernarda Pera 6-1, 6-2 in the semi-finals on Friday.
Świątek on Wednesday crashed out of the women's singles at the French Open with a quarter-final defeat to Greece's Maria Sakkari that ended the Pole's hopes of defending her title in Paris.
(pk)
Source: PAP