In 1992, she won Ford Models' Supermodel of the World Contest and was subsequently signed to the Elite Model Management and later to Trump Model Management.Tricia retired from fashion modeling in 2002 and states that all her shoots since then are related to projects or product endorsements.She has appeared in ad campaigns for Ralph Lauren, Versace, Chanel, and Giorgio Armani. Helfer has walked for top fashion shows such as Carolina Herrera, Christian Dior, Claude Montana, Givenchy, John Galliano, and Dolce & Gabbana. Helfer has graced the covers of Flare, Amica, ELLE, Cosmopolitan, Marie Claire, and Vogue, among others. She also regularly appeared in photo shoots by Maxim magazine, was the magazine's wall calendar girl for 2005, and was ranked #57 on the Maxim's Hot 100 Women of 2007.She also posed topless for the February 2007 issue of Playboy.