Flight logs show Mountbatten-Windsor and Maxwell flew from Luton to Edinburgh on Epstein’s private jet with two other passengers on 1 September 2006.
An image believed to show disgraced financier Epstein and former socialite Maxwell at Balmoral was also released by US prosecutors during her sex trafficking trial.
It is thought to have been taken in 1999, when Mountbatten-Windsor reportedly invited the couple to stay at the castle.
Epstein and Maxwell were reportedly regular guests at royal residences in the late 1990s and early 2000s.
Last year, the so-called Epstein Files were released by the US Department of Justice.
Among them was an email from someone named ‘A’ to Maxwell which said they were at Balmoral and asked for “new inappropriate friends”.
The message, sent to Maxwell on 16 August 2001, begins: “I am up here at Balmoral Summer Camp for the Royal Family.”
Later in the email, the sender asks: “How’s LA? Have you found me some new inappropriate friends?” before signing off “see ya A xxx”.