The Northern Ireland Office takes seriously its duty to maintain this important historic listed building. In the calendar year 2007 the cost of maintaining Hillsborough Castle and its grounds was £835,669. This figure covers planned preventive maintenance, basic repairs and other works to the fabric of the building and its mechanical and electrical services, such as installation of solar panels and biomass heating systems.
Activities at the castle include departmental meetings, training courses and conferences, the annual garden party and citizenship ceremonies. In addition to its use by the Northern Ireland Office and other government departments, charities and local community groups can request to use the facilities, generally for fundraising purposes, and the castle and grounds are open at certain times of the year for guided tours.
The income generated by Hillsborough Castle from its range of customers for 2007 was £184,141.