The campaign, in conjunction with Nationwide Building Society, will deliver 2.5m one-to-ones in the run up to Red Nose Day on Friday (16 March).
The ads, which launched today in high streets, supermarkets, convenience stores and London Underground stations, will feature a creative using Lenny Henry and Harry Hill, reminding customers to watch the event live on BBC1 and directing them to the Red Nose Day website.
The executions will complement messaging on other media including TV, posters and online. A reminder will also be printed on the front of every customer receipt, targeting the 600,000 or so customers expected to take a receipt.