"When we filled out the marriage license, I checked the box to change my name to Heidi Pratt," she tells Usmagazine.com exclusively. "It's on my new license, credit cards and everything."
She tells Us it was important to uphold "tradition."
"Now that we're legally married, I wanted to do the right thing," says The Hills star, 22, who tied the knot April 25 in Pasadena, Calif. "I want us to be a family in every way. When we have kids, I want us to all have the same last name."
Will she use Pratt professionally?
"Just like everything else, I'm gonna wing it," she says. "When I did my album, it was still pre-wedding, so I may still be Heidi Montag there."
Rest assured, she tells Us, "I'm Heidi Pratt now."
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