
The shop won the business after a four-way competitive pitch and will work alongside CRUK’s other roster agencies, Mother and Abbott Mead Vickers BBDO.
Atomic will now create work to increase the number of people who leave the charity a gift in their will.
Nick Georgiadis, the head of marketing for legacy and direct giving at CRUK, said it was a "big decision to appoint a creative agency" to the account "as opposed to a direct marketing agency".
Jon Goulding, a partner at Atomic, said: "With direct giving and legacy marketing responsible for over two-thirds of all CRUK’s income, we’ve got a big responsibility to deliver."