A ceremony at the Cenoptah in Queens Park on Saturday will mark Merchant Navy Day in Whanganui.
The 11am service is to commemorate all those who have served and are still serving.
Kyle Dalton, Wanganui RSA secretary-manager, said the Merchant Navy had often been an unsung service "but many who have sailed the globe under our country's colours have shown sacrifice and bravery"
"They helped keep the country afloat during wartime, and in peacetime often face challenging conditions while doing their job. Merchant Navy Day is a way to commemorate and celebrate all those who have carried out a range of roles over the years," he said.
Mr Dalton said after the service everyone is invited back to the RSA in St Hill St for comradeship and to remember old friends.