Chesterfield Borough Council will fly the Red Ensign on Merchant Navy Day to raise awareness of the UK's ongoing dependence on Merchant Navy seafarers.
The flag will fly at the Town Hall, Rose Hill on Thursday 3 September.
The council is supporting a nationwide call from the Seafarers UK charity and the Merchant Navy Association for the UK Merchant Navy's official flag to be flown on public buildings and landmark flagstaffs.
The charity's president, HRH The Earl of Wessex, has endorsed the campaign, saying: "On this Merchant Navy Day, I very much hope you will support this campaign to remember the sacrifices, salute the courage and support the future of the often unsung personnel of our Merchant Navy."
Councillor Sharon Blank, Chesterfield Borough Council’s cabinet member for governance, added: "Flying the Red Ensign on Merchant Navy Day is an opportunity for us to recognise the members of the Merchant Navy past and present, particularly those from Chesterfield, and thank them for the service they have carried out."