Remember a Charity moved the brief from Good Relations after a pitch.
As part of its remit, Frank PR will be supporting Remember A Charity's upcoming national advertising campaign.
A large part of the work includes developing ideas and executing activity around the annual awareness drive, Remember A Charity Week, which takes place each September.
In addition, Frank PR will develop content and collateral for a toolkit to be shared with member charities.
Andrew Bloch, group MD and founder of Frank PR, said: "The topic of death is not something that people necessarily want to talk or think about, or engage with, so our approach will be to drive behavioural change, get a reaction and make legacy giving a social norm.
"We’re looking to shift the taboo, not just of death but of money too. The aim is to create new ways of discussing legacies without losing the core message."