JD Wetherspoon pubs will slash their prices on Thursday 13 September to show the benefits of a VAT cut for hospitality businesses.
Chairman Tim Martin is calling on other operators to join the pub chain's UK-wide Tax Equality Day, which has already gained the support of UKHospitality and the British Beer and Pub Association.
All JD Wetherspoon pubs in England, Wales and Northern Ireland will slash the price of all food and drinks by 7.5%, while pubs in Scotland will offer the same reduction on food, soft drinks and hot drinks.
Martin, who has long campaigned for tax parity between supermarkets and pubs, said: "Pubs suffer a huge disadvantage paying about 16p in business rates per pint versus about two pence for supermarkets.
"We're aiming to make it the busiest day of the entire year in our pubs and would urge other pub and restaurant operators to participate too."
Food in pubs is subject to 20% VAT, compared to supermarkets which benefit from a 0% VAT rate on the vast majority of food products.
UKHospitality chief executive Kate Nicholls, added: "Tax Equality Day is a great way to highlight just how hospitality businesses are disproportionately hit by VAT.
"The tax disparity between the hospitality sector and supermarkets is still far too high. Pubs are paying around a third of their turnover in tax compared to a fifth for big supermarkets able to sell alcohol at very cheap prices.
"A cut in the rate of VAT for the hospitality sector can help address this unfairness and allow pubs and bars to invest in their businesses and staff members.
"We hope that everyone will support this year's Tax Equality Day and send a clear and unequivocal message to the chancellor to give the sector the VAT cut it deserves."