The actress's 8-bedroom, 11-bathroom house has reportedly been placed in foreclosure by the lender in view of Barton's $100,000 debt.
TMZ reports the former The O.C. star, 28, took out a $4.2 million loan in 2005 to purchase the $8 million home.
The actress has reportedly attempted to sell the house a couple of times, but has been unsuccessful. She also tried to lease the property for $35,000 a month in 2013, but has yet to find any takers.
Barton, who has been splitting her time between Los Angeles and London over the past few years, could lose the house if she doesn't work out an agreement with the lender soon.