Born in Cherry Hill, New Jersey,Larter is the daughter of Margaret, a realtor, and Danforth Larter, a trucking executive. She attended Carusi Middle School and later graduated from Cherry Hill High School West during her time as a model.Her parents have since moved to Allentown, Pennsylvania.

Larter began her modelling career at the age of 14 when a modelling scout discovered her on the street and was asked to star in a Phillies commercial, this led to a modeling contract with the prestigious Ford Modeling Agency in New York. Larter subsequently skipped her senior year to model in Australia, Italy and Japan, the latter a country she would temporarily settle in at the age of seventeen.

While modelling in Italy, Larter met fellow model and aspiring actress Amy Smartand the two “became instant friends”, according to Larter. A modelling job later took her to Los Angeles, whilst there, she decided to take acting classes with Smart. The two then moved into an apartment together In November 1996, Larter portrayed fictional model Allegra Coleman in an Esquire magazine hoax.When speaking about the cover and her subsequent fame, Larter said, “When the door opens for you in Hollywood, you need to run with it. You know?” Larter is currently signed to IMG Models.

During her time as a model, Larter moved to Los Angeles to pursue acting. In 2002, she moved to New York for a period of three years. In an interview withPhillymag, Larter gave reason for the move: “I took some time off to define myself outside the pressures of the industry..Part of me really needed to know if this is what I wanted to do with the rest of my life.” In January 2005, she moved to Los Angeles for a role in Heroes.

In December 2007, Larter and her then longtime boyfriend, Hayes MacArthur, were engaged to marry.They had met on the set of National Lampoon’sHomo Erectus. In a 2007 interview with Cosmo, Larter said “I told my boyfriend after three weeks that I wanted to marry him and that we could do it tomorrow”. On August 1, 2009, Larter married MacArthur in an intimate outdoor ceremony which took place at MacArthur’s parent’s estate inKennebunk, Maine.During the ceremony, guests arrived via trolleys to the sounds of Irish music playing in honor of MacArthur’s heritage,among the invited was Larter’s close friend Amy Smart. The couple later purchased a three story home in the Hollywood Hills for $2.9 million. On July 20, 2010, Larter announced that she and MacArthur were expecting their first child and later, on the September 10th episode of Late Night with Jimmy Fallon, announced that she was expecting a boy. Larter admitted that she and MacArthur left the country for Europe in an effort to hide the news of the pregnancy.Larter gave birth to the couple’s son, Theodore Hayes MacArthur, on December 20, 2010.

In an interview with Cosmopolitan, Larter “mused” on the state of her life, “I work on a TV show I love, I have the opportunity to do movies with actors I respect, and I’m in love with the man I want to spend the rest of my life with, who pushes me and excites me…There’s this fighter in me that kind of needs to be put to rest a little bit. I don’t need to be so tough to protect myself.” While speaking to Vanity Fair at the premiere of her film Obsessed, Larter spoke about her own obsessions, “I love to cook. I spend weekends reading cookbooks—it’s really my relaxation.” She has ranked ScarfaceThe Bourne IdentityBest in ShowBlue Sky and Grey Gardens as her favorite films. In June 2010, Larter was one of thousands of delegates from 130 countries who participated in a United Nations conference, ‘Women Deliver’ in Washington D.C..