Social Pub & Kitchen, part of the UK’s largest pub group, Stonegate Group, is running the offer from Tuesday, January 28, to Monday, March 17.
The chain expects to sell 130,000 pints of Guinness during the tournament.
The offer, named the Icon’s Brunch, adds Guinness and Espresso Martinis to the regular bottomless brunch.
The brunch menu includes a choice of burgers, stonebaked pizzas, nachos, and traditional brunch favourites.
The chain will also introduce a Guinness burger and Guinness chicken wings from Friday, January 31.
Stephen Cooper, head of marketing at Social Pub & Kitchen, said: “As a country of avid Guinness and rugby fans, we’re confident the Icon’s Brunch will be a hit across the UK.
“There’s nothing better than enjoying the Six Nations with a cold pint of Guinness and a delicious plate of food.
“Our bottomless brunches have always been hugely popular; we know iconic drinks like Guinness and Espresso Martini are what our guests want when watching the rugby and we are more than happy to provide this as part of the ultimate Six Nations’ experience at our venues across London.”
The Icon’s Brunch also includes other drinks such as pints of world lager, a selection of cocktails, or Prosecco.
All Social Pub and Kitchen venues will also offer a range of low and no alcohol and soft drinks.
MiXR users can unlock exclusive rewards at any Social Pub & Kitchen venue by downloading the app and creating an account, including a free drink just for signing up.
Students can also enjoy special discounts, available exclusively through the app.
The participating sites are:
– Marquis Of Wellington, Bermondsey – The Lost Hour, Greenwich – The Whitecross Tap, London – Editors Tap, Fetter Lane – Tank And Paddle, Bishopsgate – Tank And Paddle, Minster – The Cannick Tapps, London – The Garratt And Gauge, Wimbledon – Alice Houndsditch, London – Bell, Walthamstow – Bucks Head, London – Duke Of Somerset, London – Earl Of Camden – Famous Cock Tavern, Islington, London – Famous Three Kings, Fulham – Fox On The Green, Islington, London – Fox, Twickenham – Hop Poles, London – Minories, London – Temperance, Fulham – The Bay & Bracket, Victoria – The Bridge Tap, London – The Long Acre, Covent Garden – Victoria Taps, Pimlico – Vineyard, Islington, London – Prince Of Teck, Earls Court
People are encouraged to drink responsibly.