New plaques with details of servicemen killed in World War I are being hand carved for a West Sussex war memorial.
The names of 55 people not previously added to the memorial in Horsham came to light after research by a historian.
New stone wings are also being added to the site to carry the missing names in time for next year's Remembrance Day.
The memorial also carries the names of those killed in World War II, and the council said it was taking steps to add details of those from other conflicts.
Horsham District Council has urged anyone who thinks their relative should be recorded on the town's war memorial to send details in writing, along with the name of the missing person, to Horsham Museum.
It said local historian Gary Cooper had only discovered that the names of some of the servicemen and women killed during World War I were missing from the memorial when he started to write up the life stories of those already listed.
The council said it took him 25 years to track down the missing names as there was no central list.
Mr Cooper is currently researching the more accessible World War II records to identify other missing names.
Horsham District Council said it was refreshing its current recording scheme to reflect all those who have fallen in conflicts other than World War I and II.