Eating at Firehouse Subs with celiac disease, IBS or food allergies

Firehouse Subs publishes allergen and ingredient information for every part of a sub, and it now offers a gluten-free roll. But it is careful about what that roll means. As of October 2026, its gluten-free roll page says that "since other menu items in our restaurants do contain gluten, we cannot guarantee an entirely gluten-free experience."

Its US allergen disclaimer goes further for all allergens: "Although efforts are made to avoid cross-contact of allergens, Firehouse Subs does not guarantee that cross-contact with allergens will not occur." It asks you to inform staff before ordering if you or anyone in your party has a food allergy.

So this guide doesn’t point to choices that are free from risk. It summarizes what Firehouse Subs’ own pages say about gluten, the major allergens and common FODMAP sources, and what to ask when you order.

As of October 2026, Firehouse Subs says the gluten-free roll is:

• Available on a medium sub only, for an additional charge.
• Offered at all US and Canada locations, excluding non-traditional locations such as airports and universities.
• Not a guarantee of a gluten-free meal, because other menu items in its restaurants contain gluten.

Its interactive nutrition menu lists two gluten-free breads under medium sub bread: a Gluten Free Hoagie Roll (made with tapioca and potato starches, brown rice flour and psyllium) and a Gluten Free Ciabatta Roll (made with corn starch, corn flour, rice flour and soy protein). The ciabatta entry marks soy and sesame and adds "may contain mustard and sesame". It also repeats that its restaurants use bread with gluten, so Firehouse cannot guarantee a gluten-free experience. The roll page itself refers to a single gluten-free roll, so ask which one your location carries.

Even with a gluten-free roll, everything else on the sub comes from the same line as the wheat rolls. The NIDDK explains that cross-contact can happen when food is prepared or served, and suggests telling your server you have celiac disease and asking how food is made. Whether a shared sub line is an acceptable risk is a decision to make with your gastroenterologist or dietitian. Our guide to gluten-free vs celiac-safe explains the difference.

From Firehouse Subs’ US nutrition menu as checked in October 2026, these are marked for wheat and gluten:

• The white and wheat sub rolls. The white roll’s ingredients also include malted barley flour, which the Celiac Disease Foundation lists as a source of gluten.
• Meatballs, which contain wheat breadcrumbs, and are also marked for milk and soy. The menu flags the medium meatball sub with "contains gluten", so changing the roll doesn’t remove gluten from that sub.
• Tomato bisque (also milk) and chicken noodle soup (also egg and soy).
• Cookies and the brownie, which are also marked for milk, egg and soy.

Several items had no wheat or gluten marked when we checked, including the steak, chicken breast, roast beef, smoked turkey, honey ham, the cheeses, the fries and the chili. That describes their ingredients, not freedom from cross-contact, and Firehouse’s nutrition menu doesn’t say how fries are cooked or what shares that equipment. The Celiac Disease Foundation notes that fries can pick up gluten from shared fryer oil, so ask at your location.

These examples come from Firehouse Subs’ US nutrition menu as checked in October 2026. They describe what Firehouse lists, not recommendations, and they can change.

Two details stand out. First, Firehouse’s nutrition portal carries a supply note that, due to a temporary change in supply, its mushrooms may now contain fish (anchovies), soy and sulfites, while the mushroom entry itself marks only soy and sulfites. If you have a fish allergy, treat the portal note as the one to follow and ask in store. Second, fish appears in places you might not expect: the sweet mustard and the coleslaw.

The allergen menu tracks the nine major US allergens plus gluten, MSG, nitrates, and two Canadian categories (seeds, which includes mustard seed, and sulfites). Firehouse notes that its chips and sides don’t contain tree nuts or peanuts but are made in a facility that uses them in other products.

Firehouse Subs says it does not consider soybean oil an allergen, because refined oil doesn’t contain measurable soy protein. The FDA likewise excludes highly refined oils from its major food allergen labeling rules.

Firehouse still recommends that people with a soy allergy ask their doctor whether to avoid soybean oil. If your doctor says yes, Firehouse lists these to avoid: all bread products, meatballs, marinara, brownies, all cookies, Rice Krispies, soups, au jus peppers and onions, all mayo and all salad dressings.

Based on Firehouse Subs’ US ingredient lists as of October 2026:

• Garlic and onion: in the steak seasoning, chicken breast, au jus mushrooms, marinara, Cajun seasoning and Cajun fries, chili, ranch, Italian dressing, chipotle honey dressing and sweet mustard. Onion also appears in the au jus peppers and caramelized onions, and the "garlic blend" is garlic powder and garlic salt.
• Wheat: in the regular rolls, meatballs, soups, cookies and brownie.
• Honey and high fructose corn syrup: honey in the ham, honey mustard and chipotle honey dressing; high fructose corn syrup in the marinara and Italian dressing.
• Mushrooms and kidney beans: the au jus mushrooms, and kidney beans in the chili.
• Lactose: in cheese-heavy subs, the ranch and the tomato bisque.

Monash University lists garlic, onion, mushrooms, most legumes, wheat-based breads, honey and high fructose corn syrup among higher-FODMAP foods, and lettuce, cucumber, potato, carrot, green bell pepper and hard cheeses among lower-FODMAP ones. A plain meat with lettuce, tomato and a simple oil-and-vinegar might suit some people better than a sauced sub, but the meats themselves are seasoned, so check each one. Only you and your dietitian know your own triggers, and portion size matters too. Our guides to hidden garlic and onion and FODMAP portion sizes explain more.

1. Check the allergen and nutrition menu online first for every part of the sub: roll, meat, cheese, toppings and sauce.
2. Tell the team at the start, as Firehouse asks, even if you’re ordering in the app.
3. Ask for a glove change and fresh utensils, and ask whether toppings can come from fresh containers rather than the open line.
4. If you avoid gluten, ask which gluten-free roll they have and how it is stored, steamed and sliced.
5. Ask how the fries are cooked and what else goes in that fryer, since Firehouse’s menu doesn’t say.
6. If you’re unsure, skip it. It’s fine to choose a simpler sub or eat somewhere else.

Helpful phrases: "I have celiac disease. Which gluten-free roll do you have, and can you change gloves before making my sub?" and "I have a fish allergy. Do your mushrooms or sauces contain anchovies today?" Our guide to talking to restaurant staff about allergies has more, and our Subway and Jersey Mike’s guides cover similar sub-shop questions.