Leo Burnett, TBWA\London, The Union and Rainey Kelly Campbell Roalfe/Y&R are pitching for the brand, which the brewer acquired earlier this year as part of the Bulmers drinks portfolio.
Bulmers consolidated all of its brands, bar San Miguel, into Leo Burnett in June.
San Miguel was previously promoted with advertising through Abbott Mead Vickers BBDO. The most recent campaign for the brand broke in April using national cinema and regional TV concentrating on the North of England.
San Miguel, Britain's best-selling Spanish beer, competes mainly with premium rivals such as Grolsch, Staropramen and Leffe. Its advertising has focused heavily on Spanish culture and lifestyle, which was regarded as aspirational, as well as capitalising on the fact that Spain attracts 14 million British holidaymakers each year.
S&N has confirmed that investment in the brand would be maintained following the pitch. However, it remains unclear if marketing support will be extended to the South.
Earlier this year the San Miguel packs were redesigned to reinforce the brand's "Spanish passion for life" message alongside images of Spanish festivals.
S&N finalised its purchase of the Bulmers drinks business six months ago.