The drive, through Tullo Marshall Warren, is targeting more than 300,000 customers held on the Guinness customer relationship marketing database.
It aims to highlight the fact that consumers can start the celebrations over the weekend, and to make sure that if they do go out revelling, Guinness will be the drink they choose over its rivals.
Alice Woodwark, Guinness relationship marketing manager, said: "This campaign is a great example of how direct marketing can be used to build greater consumer loyalty through communicating brand values and delivering rewards, while leveraging on-trade activity and drive footfall in bars and pubs around the country."
Consumers whose details are held on the Guinness relationship marketing database have been contacted via a direct marketing campaign through Tullo Marshall Warren and its digital arm, digital TMW.
A direct mail pack targeting 300,000 includes a Guinness-branded pint carrier, to help people carry their drinks without spilling them.
A further 60,000 customers will be targeted via email. This directs recipients to and the Guinness party maker, developed by Carlson Marketing Group, which enables customers to create a digital St Patrick's Day band, which they can email to their friends.
The drive also includes details of all the promotions Guinness is running in pubs on Saturday March 15, which have been developed by sales promotion agency Triangle Communications.
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