The Daily Mail Friday reported details of the settlement are contained in a preliminary London High Court judgment sent to the former couple and their lawyers this week.
The official decision is expected to be handed down Monday.
McCartney and Mills were married for four years, split up in 2006 and have a 4-year-old daughter together.
The couple was not able to reach a divorce settlement last month and so a decision regarding the division of their assets was to be made by a judge. The divorce hearings were held in private.
McCartney is said to be worth about $1.6 billion.