Firehouse Subs uses its signature toasted sub roll —available in white or wheat —for the Tuna Salad sandwich. The roll is a proprietary “private recipe” sub roll that’s toasted (and for most hot subs, steamed with the meats/cheeses; the tuna sub is served cold but the bread is still toasted).

What the bread actually is

  • Type: Sub roll (hoagie-style), offered as White or Wheat at no upcharge on the Tuna Salad sub.
  • Preparation: The roll is toasted , which gives it a light crunch that contrasts with the creamy tuna salad.
  • Branding: Firehouse describes its bread as a “toasted private recipe sub roll” used across the menu.

Some fan sites and copycat recipes simply call it an 8-inch sub roll when recreating the sandwich at home, reflecting the standard hoagie shape and size used in-store.

How it’s built on that roll (context for the bread choice)

The Tuna Salad sub is layered with:

  • Tuna salad (tuna, mayo, celery, and seasonings; some versions note relish/mustard/black pepper)
  • Provolone cheese
  • Lettuce, tomato, onion, plus mayo and spicy deli mustard
  • Served with a pickle spear

Because the sandwich is cold (unlike most Firehouse subs), the toasted roll provides texture without steaming the fillings.

If you’re making it at home

To mimic Firehouse’s build:

  • Use an 8-inch white or wheat sub/hoagie roll
  • Lightly toast the inside faces
  • Add provolone, then a generous scoop of tuna salad, then veggies and condiments as above.

TL;DR: Firehouse Subs’ Tuna Salad sandwich rides on its standard toasted white or wheat sub roll (a private-recipe hoagie-style roll).

Information gathered from public forums or data available on the internet and portrayed here.