Roadhouse King from Burger King: Allergens at a Glance
The honest verdict
Roadhouse King · Burger King
The Roadhouse King is a double cheeseburger topped with bacon, crispy onion rings, and smoky BBQ sauce on a sesame seed bun. Its allergen profile is anchored by wheat from the bun, milk from the cheese and mayo, egg from the mayonnaise, soy from the bun and mayo, and sesame from the seeded bun. The onion rings add a second wheat source and potential fish cross-contact if fried in shared oil. Peanut, tree nut, fish (by ingredient), and shellfish are not typical ingredients. The Roadhouse King is a specialty burger distinct from the Whopper (flame-grilled with tomato/lettuce) and the Bacon King (no onion rings). Always confirm with your specific Burger King location before ordering.
Allergen details change and vary by location. This is a general guide — always confirm with the restaurant before ordering. Not official or medical advice.
Key facts
The Roadhouse King bun is a sesame seed bun, making sesame a direct ingredient (not cross-contact) under the FASTER Act.
FDA — Food Allergen Labeling and Consumer Protection Act (FALCPA)
Burger King's mayonnaise contains egg and soybean oil, adding two allergen sources beyond the burger patty and bun.
Onion rings add a second wheat source and potential fish cross-contact risk from shared fryers at locations serving the Big Fish sandwich.
Every major allergen, one clear grid
Each of the nine major allergens marked for Roadhouse 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.
- MilkContains
Milk is present in the cheese slices (American cheese) and likely in the mayonnaise. The bun may also contain milk or butter. This is a dairy-heavy item.
- EggContains
Egg is present in the mayonnaise used on the sandwich. Some bun recipes may also contain egg. Confirm the specific mayo recipe with Burger King.
- Wheat / GlutenContains
The sesame seed bun and the crispy onion rings both contain wheat/gluten. This is a double-wheat item. There is no standard gluten-free bun option at most locations.
- SoyContains
Soy is present in the mayonnaise (soybean oil) and likely in the bun (soy flour or lecithin). The BBQ sauce may also contain soy. Refined soybean oil is FDA-exempt but still a concern for some with soy allergy.
- PeanutFree
Peanut is not an ingredient in the Roadhouse King or its components. Cross-contact is very unlikely in Burger King kitchens.
- Tree NutFree
Tree nuts are not an ingredient in this sandwich. Not a concern for this menu item.
- FishFree
Fish is not an ingredient in the Roadhouse King. However, if the onion rings share a fryer with fish items (like the Big Fish sandwich), trace cross-contact is possible.
- ShellfishFree
Shellfish is not an ingredient in this sandwich and is not typical in Burger King fryer environments.
- SesameContains
The bun is a sesame seed bun. Sesame is a top-9 allergen under the FASTER Act. This is a direct ingredient, not cross-contact.
“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.
Small changes that remove an allergen
Simple modifications that can take an allergen off your roadhouse king. Always name your allergy when you order and ask staff to confirm — a modification only helps if the kitchen prepares it separately.
Order without cheese
Order without mayonnaise
Request a lettuce wrap instead of the bun
Order without onion rings
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.
Read this before you order
Cross-contact & severe allergies
A “free of” mark on the grid above means the allergen isn't an ingredient — it doesn't mean the item was made in an allergen-free kitchen. Two things matter most:
Shared fryers & equipment
The onion rings on the Roadhouse King are fried items, and Burger King kitchens use shared fryers. If the same oil is used for fish items (Big Fish sandwich), trace fish protein can transfer to the onion rings and then to the burger. Bun preparation surfaces may also contact other allergens. Cross-contact risk is present for wheat, fish, and soy. Ask your location about fryer separation.
If your allergy is severe
For anaphylactic allergy to wheat, milk, egg, soy, or sesame, the Roadhouse King is a high-risk item with multiple direct allergen sources. Removing the bun, cheese, and mayo individually can reduce risk, but cross-contact on shared grills and fryers remains. Carry your epinephrine auto-injector. If you cannot confirm preparation details, consider a simpler burger option with fewer components.
This guidance is general and can't account for how any single location prepares your food. The restaurant's staff and official allergen menu are the final word — when in doubt, ask, or choose something else.
❓Frequently Asked Questions
No. The sesame seed bun and crispy onion rings both contain wheat/gluten. There is no gluten-free version of this sandwich at Burger King. A lettuce wrap removes the bun, but the onion rings remain a wheat source. If you remove both the bun and onion rings, you are left with a double cheeseburger patty with bacon and BBQ sauce — confirm the sauce is also gluten-free.
Yes. The American cheese slices are a direct dairy source. The mayonnaise may also contain milk or milk derivatives. The bun may contain butter or milk. This is a dairy-heavy item. Removing the cheese removes the largest dairy source, but the mayo and bun may still contribute.
The Whopper has tomato, lettuce, pickles, and ketchup — no onion rings, no bacon, and no BBQ sauce. The Roadhouse King adds crispy onion rings (wheat + potential fish cross-contact), bacon (may contain soy or smoke flavoring), and smoky BBQ sauce (may contain soy). Both share the sesame seed bun and mayonnaise base. The Roadhouse King has more potential allergen sources due to the onion rings and sauce.
No, not safely. The bun is a sesame seed bun, and sesame is a direct ingredient (not cross-contact). There is no standard bun substitution at Burger King that removes sesame. If you have a sesame allergy, you would need to remove the bun entirely and use a lettuce wrap or eat the patty and toppings separately.
Burger King uses shared fryers for most fried items. If your location serves the Big Fish sandwich, the onion rings may share fryer oil with fish. This is a cross-contact risk, not a direct ingredient. Ask your specific location whether they use dedicated fryers for onion rings versus fish items.
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Read moreFind out which foods you actually react to
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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.