The campaign, created by Iris, will target 100,000 homes in the UK and will also be supported by online activity and point of sales in all 90 branches.
The bank said that The Smart Saver account, which pays 4% gross/AER, has been simplified to make it easier for customers to use, claiming that British people save half the amount that other Europeans do.
The direct mail pack contains a cardboard piggy bank with details of four ways to start saving into the account by phone, online, by post or at a Co-operative Bank branch.
David Morley, director at Iris, said: "Our creative aim was to position the utility of the savings account as an easy and hassle-free way to kick-start your savings."
The creative team consists of copywriter Mark Lawson and art director Kevin Boyd.
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