"He has no need or desire to make their relationship official in the eyes of the law," the source told the website.
"Kanye prefers the idea of them as 'partners.' He sees marriage as outdated and he's all about embracing the modern and the new. He doesn't feel like he has to marry Kim just because they have a daughter together."
In August, sources told Us Weekly that Kardashian and West were planning a "secret" possible "destination wedding," as West wanted their big day to be "over the top" since he's never gotten married before.
"They've been discussing marriage for a while," a source told Us at the time. "A wedding is in the works."
Added a West friend, "He wants to get married more than she does!"
"I found what I really wanted. So I think I definitely do want that," Kardashian said of exchanging vows with West shortly after she had finally reached a divorce settlement with Humphries following months of court proceedings and legal battles over their 72-day marriage.
A source also told Us in January that West was "dying to propose" to his then-pregnant girlfriend. However, the fact Kardashian was still legally married to Humphries at the time prevented the rapper from popping the question.