Each year, the Boyle family organizes a thematic masquerade ball on their estate. Selected aristocrats from the Imperial Court and other persons of importance are invited for a night of music and dance, and a chance to mingle. Per tradition, the Emperor or Empress are the first to receive an invitation, but have to decline, as it would be improper for them to join such event.
For the invited members of the Imperial Court, preparations are made two weeks before the event, with tailors and seamstresses being invited to the Great Hall in Dunwall Tower to present models of costume to be hand-tailored for the guests. The Boyle Masquerade continues to be the subject of topics of the aristocracy for the next two weeks after the event. To not receive an invitation is also a matter of gossip.
- The Boyle Masquerade is shown twice in the Dishonored series:
- The 1837 event in Dishonored, upon which Lady Waverly Boyle (the canonical mistress of Hiram Burrows is kidnapped by Lord Brisby. It took place on the 28th day of the Month of High Cold.
- The 1851 event in Dishonored: The Corroded Man, during which the new Whalers attacked the Boyle Mansion in order to break into its vault, and during which Lady Lydia Boyle is killed. It took place on the 15th day of the Month of Darkness.
- Tailors from Drapers Ward used to provide costumes for the event before its fall during the Rat Plague. Waverly Boyle was still able to order three for her and her sisters from the Dressmaker for the 1837 party. By 1851, Drapers Ward restored its reputation as a fashion district, and half of the seamstresses and tailors preparing costumes were contracted from there.
- The event can count on more than a hundred guests, with the 1851 ball being the biggest in recent years.
- In an unused invitation note for Bunting in Dishonored, the 1837 Boyle Masquerade had the theme "Living Well in Terrible Times". The event was also named the "Annual Boyle Estate Costume Ball".