U.S. brides — outside of big cities — on average spend less than $2,000 on a wedding dress, Landgraf and Greenberg estimate. American-made dresses tend to start around twice that price.

Most wedding dresses are made in China, so tariffs are a new worry for brides. At David’s Bridal, the largest seller of gowns in the United States, its chief executive, Kelly Cook, is trying to ...