Alex Morgan scored her third career hat trick, while Tobin Heath and Carli Lloyd also scored. Youngsters Mallory Pugh, Lindsey
Horan and Morgan Brian contributed with a combined four assists.
The USA, which faces Canada in Sunday's final, has won its first four games by a margin of 21-0 and has outshot its opponents by 98-6.
Feb. 19 in Houston
USA 5 Trinidad & Tobago 0. Goals: Heath 12, Morgan 30, 71, 73, Lloyd 43.
USA -- Solo; O'Hara, Johnston, Sauerbrunn, Klingenberg; Brian, Horan (Mewis, 60), Heath, Lloyd (Dunn, 66), Pugh (Press, 59); Morgan.
Trinidad & Tobago -- Kimika Forbes; Cunningham, Blair, King, Debesette, Swift (Francois, 68), Attin-Johnson, St. Louis (Shade, 72), Mollon, Karyn Forbes, Cordner.