Spears is working with one of the Caesar group properties on the deal, TMZ said.
"The deal is a go. There are several stipulations that could throw a monkey wrench in the deal, but it's basically done," said a source connected to the negotiations.
The details of the agreement are still up in the air, the source said, adding that Spears' i likely to be paid more than $100 million a year.
Celebrity Families of 2014 [PHOTOS]