The former Hills star has been dating William for just over a year, but she has confirmed that they will not be tying the knot anytime soon.
Speaking on American radio show, On With Mario Lopez, Lauren exclaimed, "I'm not engaged!" when asked about the whispers.
Host Mario then chatted to Lauren about her love for 'bucket lists' and asked if getting married and having kids was on hers.
"Not for this summer," she said. "It's more like...take a trip and get a suntan!"
While on the subject of weddings, Mario asked Lauren if she was going to the forthcoming nuptials of former Laguna Beach and The Hills co-star Kristen Cavallari.
Laughing, Lauren replied: "Oh, you know, my invite must have gotten lost in the mail..."
Lauren also spoke about the theory that all of The Hills was entirely scripted, adding that it was very real for her.
"My experience was, this was my life, these were the people I lived with, this was my job, this was my boyfriend," said Lauren.
"It's very difficult to say that this was a fake show - if it was, I didn't know!"
You can listen to the full interview with Lauren by clicking here!
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