The Band of the Kings Division and the Royal & Derngate Community Choir, will be Beating Retreat at St Andrew’s Hospital.
Beating Retreat is a military ceremony that dates back to an order given to the army of James II for troops to beat drums and parade to mark the end of a day of combat, the lowering of the flags and the closing of the gates.
It was marked by the sound of the evening gun.
This has now evolved into a flag-lowering ceremony.
The invitation event will begin at 7.15pm and will be in aid of two military charities, the Northamptonshire Army Benevolent Fund (ABF) and Northamptonshire Soldiers, and Sailors, Airmen and Families Association (SSAFA).
A spokesman for the ABF said: “Being more of a ceremony, it is a great opportunity to bring people together to enjoy the wonderful spectacle of a Military Marching Band.
“St Andrew’s Hospital has kindly agreed for this ceremony to take place in their impressive grounds right in the heart of Northampton.”
The Beating of Retreat will be preceded by a short reception and followed by a drinks party with entertainment from the Royal & Derngate Community Choir in the Great Hall at St Andrews Hospital.