The store, located in Brighton Square, has blamed "basic economics" for the closure.
Rounder opened in 1966 and has in recent years proudly boasted the claim: "Still independent, still number 1."
Owner Phil Barton said today: "The shop and the staff have always striven to be the best. We are not able to deliver the best anymore and with the deepest regret I have to close the doors at the end of July.
"Rounder has been a part of my ...