The Revolution bar in Bridge Street is to have an extra bar added and a new-look outdoor area.
It will be closed for just a week from this Saturday and will reopen at noon on Saturday July 12.
A spokeswoman said: “The focus of the refurbishment is on improving the overall quality of the interior and providing a stronger differentiation between the drinking and dining offering
“We want it to be able to provide the perfect setting for long lunches, after work cocktails and late-night partying.”
As well as table service. the bar will also be introducing a full food menu.
A re-launch event will start at noon on July 12 with a free BBQ on the terrace, and from 6pm guests can enjoy canapés, cocktails, live music, DJs and other entertainment.
Guests will also be able to take part in a mini-cocktail making master-class.
Seamus Burke, the bar’s general manager, said: “We are looking forward to welcoming back existing customers to our new-look venue, and we hope the changes we have made will also encourage new custom. We have received an extensive investment which is really exciting for us, and will be really evident when you see the finished product.”