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Allergens at a glanceLast verified July 2026

Bacon King: Allergens at a Glance

The honest verdict

Bacon King · Burger King

The Bacon King is a double cheeseburger topped with bacon, served on a sesame seed bun. It contains wheat from the bun, milk from the American cheese, egg from the mayonnaise, and soy from the refined soybean oil used in the mayo and for frying. Sesame is present on the bun. Peanut, tree nut, fish, and shellfish are not typical ingredients. Cross-contact on shared grills and fryers is possible. This sandwich is distinct from the Whopper (which includes tomato, lettuce, onion, pickles, and ketchup) and the Bacon Double Cheeseburger (which uses a different bun and sauce). Always confirm with your specific Burger King location before ordering.

5
Contains
0
May contain
4
Free of
Burger KingFast-food menu itemSee the full allergen matrix

Allergen details change and vary by location. This is a general guide — always confirm with the restaurant before ordering. Not official or medical advice.

All 9 allergens
The full FDA Big-9, marked
Cross-contact
Shared-fryer risk called out
Verify-first
Defers to the official menu
Verified July 2026
Updated as recipes change

Key facts

The Big-9, answered

Every major allergen, one clear grid

Each of the nine major allergens marked for Bacon King at Burger King — Contains, May contain (cross-contact or varies), or Free. Anything we couldn't confirm defaults to "may contain," because a shared kitchen can't be ruled out without the restaurant's official menu.

ContainsMay containFree
  • Milk
    Contains

    American cheese is a standard topping on the Bacon King. Milk is a primary ingredient in the cheese. Some locations may offer a dairy-free modification by removing the cheese, but the sandwich is typically served with cheese as standard.

  • Egg
    Contains

    Mayonnaise is a standard condiment on the Bacon King. Eggs are a primary ingredient in mayonnaise. Removing the mayo removes the egg source, but confirm the bun and other toppings do not contain egg.

  • Wheat / Gluten
    Contains

    The Bacon King is served on a sesame seed bun made from wheat flour. There is no standard gluten-free bun option at Burger King. The bun is the primary wheat source.

  • Soy
    Contains

    Refined soybean oil is used in the mayonnaise and for frying the bacon and beef patties. Highly refined soy oil is FDA-exempt from allergen labeling and tolerated by most with soy allergy, but those with severe soy sensitivity should confirm the oil type used.

  • Peanut
    Free

    Peanut is not an ingredient in the Bacon King or its components. Burger King does not use peanut oil in standard fryers. Cross-contact is very unlikely.

  • Tree Nut
    Free

    Tree nuts are not an ingredient in the Bacon King or its components. No tree nut oils or toppings are used.

  • Fish
    Free

    Fish is not an ingredient in the Bacon King. Burger King does not typically fry fish items in the same fryers used for bacon or beef patties, but cross-contact is possible if the restaurant serves the BK Fish Sandwich in shared fryers.

  • Shellfish
    Free

    Shellfish is not an ingredient in the Bacon King and is not typical in Burger King kitchens.

  • Sesame
    Contains

    The sesame seed bun is a standard component of the Bacon King. Sesame seeds are applied to the top of the bun. Removing the bun removes the sesame source, but the sandwich is typically served with the seeded bun.

“May contain” means cross-contact is possible or the answer varies by location — not that the allergen is a listed ingredient. For a severe allergy, treat “may contain” the same as “contains” until the restaurant confirms otherwise.

Order it safer

Small changes that remove an allergen

Simple modifications that can take an allergen off your bacon king. Always name your allergy when you order and ask staff to confirm — a modification only helps if the kitchen prepares it separately.

Order the Bacon King without cheese

Removesmilk from American cheese

Order the Bacon King without mayonnaise

Removesegg and soy from mayonnaise

Request the sandwich without the bun (lettuce wrap or bowl)

Removeswheat from the bun and sesame from the seeded bun

Ask for a fresh batch of bacon cooked in a dedicated fryer

Removespotential cross-contact from shared fryer oil

A modification lowers exposure but doesn't erase cross-contact from shared fryers, grills, or prep surfaces. For a severe allergy, confirm the prep with a manager before you eat.

Frequently Asked Questions

Yes, the Bacon King contains dairy from the American cheese. Milk is a primary ingredient in the cheese. Removing the cheese removes the dairy source, but confirm the bun and other toppings do not contain dairy. Burger King's sesame seed bun is typically dairy-free, but cross-contact on shared grills is possible.

No, the Bacon King contains wheat from the sesame seed bun. There is no standard gluten-free bun option at Burger King. Removing the bun and ordering the sandwich as a lettuce wrap or bowl removes the wheat source, but cross-contact on shared grills with breaded items is possible.

Both sandwiches contain wheat (bun), milk (cheese), egg (mayo), soy (mayo oil), and sesame (seeded bun). The Bacon King adds bacon (cooked in shared fryers) and uses a different sauce profile — the Whopper includes ketchup, tomato, lettuce, onion, and pickles, which are typically allergen-free. The Bacon King's bacon introduces an additional cross-contact risk via fryer oil. The core allergen profile is very similar, but the bacon adds a variable.

Yes, the Bacon King contains soy via refined soybean oil used in the mayonnaise and for frying the bacon and beef patties. Highly refined soy oil is FDA-exempt from allergen labeling and tolerated by most with soy allergy, but those with severe soy sensitivity should confirm the oil type used. Removing the mayonnaise reduces but does not eliminate soy exposure.

The sesame source is the seeded bun. Removing the bun removes the sesame. You can order the sandwich as a lettuce wrap or bowl without the bun. Confirm with the restaurant that no other components (sauce, toppings) contain sesame. Burger King's standard mayonnaise and cheese do not contain sesame.

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Explore allergy testingTesting identifies sensitivities — it doesn't make any fast-food item safe to eat, and it isn't emergency care. For a severe allergy, always confirm prep with the restaurant and carry your epinephrine.

Please verify before ordering

Allergen info changes and varies by location

Recipes, suppliers, and preparation methods change often and differ between locations, so the details here can go out of date or not match your specific Burger King restaurant. Always confirm directly with the restaurant and check its official allergen menu before ordering. This page is a general research summary — it is not official information from Burger King, and it is not medical advice. If you have a food allergy, decisions about what is safe to eat should be made with the restaurant and, where relevant, your healthcare provider.

Last verified July 2026Burger King and related marks are trademarks of their respective owners, used here only to identify the menu item.

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