List of passenger ships built in the United States

As a result of the Merchant Marine Act of 1920, only ships built and registered in the United States are permitted to sail solely between ports in the United States. The Merchant Marine Act of 1928 would continue to incentivize and spur the construction of U.S. built ships through government loans, which would lead the International Mercantile Marine Company and along with other U.S. run shipping lines to order new ships through up through World War II. 
The largest passenger liner built in the United States to date is the SS "United States", completed in 1952. The last large passenger liner to be completed in the United States was Moore-McCormack Lines' SS "Argentina" in 1958.
The only US-built passenger deep water ships still in existence today are the SS "United States" (laid up), former converted cargo liner "SS Medina" (hotel ship), and the partially US-built "Pride of America" (still in service). Today, only small coastal and river passenger ships are still built in the U.S. and fly the American flag.
Shipyards.
The primary yards that were building passenger ships in the 20th century include: