Burger King is celebrating Mushroom Day with a 1-for-1 offer on its beloved Mushroom Swiss burgers, available from 12 to 17 October 2025. Fans of the iconic mushroom-and-cheese combo can enjoy double the flavour at no extra cost, with three delicious options across different mealtimes.
Start your morning right with the Mushroom Swiss Croissan’wich® with Egg — a warm, flaky croissant layered with juicy mushrooms, melted cheese, and a perfectly cooked egg. Available during breakfast hours only, simply key in Code: SHROOM11 when ordering to enjoy the 1-for-1 deal.
If you’re craving something heartier for lunch or dinner, take your pick between two all-time favourites:
The Single Mushroom Swiss, featuring a flame-grilled beef patty topped with Burger King’s signature mushroom sauce and Swiss cheese (Code: SHROOM22).
The Mushroom Swiss Tendergrill®, a juicy grilled chicken burger with the same creamy mushroom sauce that fans love (Code: SHROOM33).



