The name refers to a pre-decimalisation currency unit of one old pound and one shilling, much favoured by up-market establishments and professionals; the pub used to have a fascia showing "Ye Olde One Pound One". Now it is a small mews pub with its own renowned “Guinea Grill” restaurant, which has become a destination pub restaurant and for which booking is advisable; the restaurant has a meat fridge from which customers can select their own cuts as they enter. The bar area itself has limited seating and can get a bit cramped when busy. It's reputed there has been an inn on this site since 1473 (highly unlikely). The present pub was built in 1741, licensed in 1754 and altered over the years; it now shows interesting evidence of how a Victorian pub would have been subdivided by class. Unsurprisingly in this area the clientele tends to be upmarket and ale prices reflect this.
Second-placed in the Evening Standard Top 50 Pubs 2019, and within the top 15 in 2020 and 2021 in the Estrella Damm national Top 50 Gastropubs awards; also listed in the ED National Restaurant Awards.