The HAC has a ceremonial role which is fulfilled by both the Regiment and the Veterans of the Company.
The Regiment furnishes Guards of Honour for members of the Royal Family and for visiting Heads of State or Commonwealth Prime Ministers. There are normally two State Visits per year and on each occasion the Lord Mayor holds a banquet in the visitor's honour. The Head of State is welcomed at the entrance to the Guildhall by the HAC Guard of Honour.
In 1924, when the Regular detachment from the Royal Artillery stationed at HM Tower of London was disbanded, the HAC took over the task of firing the salutes from this Royal Fortress. The Regiment's saluting Detachment is equipped with the 105mm Light Gun.
When members of the HAC Regiment have completed their term of service with the Territorial Army but wish, in some way, to continue to serve in an organisation of a military character they have the option, provided they remain as members of the Company, to join the Company of Pikemen & Musketeers or the Light Cavalry.
The Company of Pikemen & Musketeers was established in 1925 and received a Royal Warrant 30 years later in 1955. This Warrant lays down their organisation, numbers and duties. It is an entirely voluntary, unpaid organisation. It is deemed a privilege to be a member and there is a waiting list of members of the Company who wish to join the ranks. The Pikemen and Musketeers wear the uniform of the period of Charles I and can be seen at State and civic occasions. They serve as the Lord Mayor's bodyguard.
The Light Cavalry is a more recent addition to the voluntary, unpaid ceremonial units of the HAC. It was formed in 1979 and, in 2004, received a Royal Warrant from HM The Queen. The Light Cavalry differs from the Pikemen & Musketeers in that it is open to other than Veteran members of the Company; those known as Non-Regimental Members may also join. The Light Cavalry fulfils a similar ceremonial role to the Pikemen & Musketeers but with the added glamour of mounted soldiers. The cavalrymen serve as the escort to the Lady Mayoress at the Lord Mayor's Show.