The retained 12-month briefs were won following two separate competitive pitches.
This is the first time an agency has been used for consumer brand PR on Carling.
Red will create a campaign around Carling's 'sociability' message that is currently being promoted through advertising. It will also handle new product launch stories.
The account is believed to be worth six figures and will be led by deputy MD Ed Staples.
Red will also handle a media relations and digital campaign for Coors Light, kicking off this summer. It will target both males and females emphasising the drink's lighter taste.
Like all drinks makers, Coors has to contend with moves to clamp down on the marketing of alcohol.
Staples said that Red would need to ensure the tone of its messaging was 'just right'.