What's the Healthiest Sub at Firehouse Subs?

November 8, 2025 •

4 min read

According to nutritional data, many fast-food subs can contain over half a person's recommended daily sodium intake in a single meal. While Firehouse Subs is known for its hearty, fully-loaded sandwiches, it's possible to find or create a much healthier option. So, what's the healthiest sub at Firehouse Subs? Your best bet is to customize a small sub with lean protein and plenty of vegetables.

Quick Summary

This article provides a comprehensive guide to finding the most nutritious options at Firehouse Subs. It highlights the lowest-calorie menu items, explains how to build a healthier, customizable sub, and compares the nutritional value of popular selections to help you make informed choices.

Key Points

Start with the Small Wheat Sub: The small sub on a light wheat roll is the best base for a healthy meal at Firehouse Subs.
Choose Lean Protein: Opt for smoked turkey or grilled chicken breast to minimize fat and maximize protein.
Ask for Extra Veggies: Loading up on lettuce, tomatoes, onions, and bell peppers adds fiber and nutrients with minimal calories.
Limit High-Calorie Add-ons: Skip the standard mayo, or ask for light mayo and minimal cheese to reduce fat and calories.
Consider the Side: Opt for a Firehouse Chopped Salad or Chicken Noodle Soup instead of chips for a more balanced meal.
Use the Nutrition Calculator: For full control, utilize the online nutrition calculator to see the impact of your customizations.

Navigating the Firehouse Subs Menu for Health

While Firehouse Subs has a reputation for indulgent, flavor-packed sandwiches, the menu offers a surprising degree of customization that can significantly impact your meal's nutritional profile. By understanding which items to select and how to modify them, you can enjoy a delicious meal that aligns with your health goals. The key is to prioritize lean proteins, minimize high-calorie condiments, and choose the right size and bread.

The Healthiest Pre-Built Subs

For those who prefer not to build their own, Firehouse Subs offers a few menu items that are relatively lower in calories and fat, particularly if you opt for the smaller size. The Engineer sub on wheat is a standout choice, featuring smoked turkey breast, Swiss cheese, sautéed mushrooms, and onions. The small version provides a balanced mix of protein and carbs without excessive calories, and you can further reduce fat by omitting the cheese or swapping standard mayo for light mayo. Other lighter options may include the now-retired 'Hearty & Flavorful, Under 500 Calories' menu items, which featured sandwiches like the Hook & Ladder Light and Turkey Salsa Verde. While these specific sandwiches may no longer be available, they demonstrate the kinds of modifications that lead to a healthier outcome: smaller buns, lean meats, and lighter sauces.

The Ultimate Guide to Building Your Own Healthy Sub

Creating your own sub is the most effective way to control your meal's nutritional content. Here's a step-by-step approach to building the healthiest sub possible:

Start with the right bread: Opt for the smaller, light wheat roll, which typically has fewer calories and less sodium than the classic white roll. A gluten-free ciabatta roll is also available for those with dietary restrictions.
Select a lean protein: Choose smoked turkey breast, grilled chicken breast, or Virginia honey ham. These are much leaner than high-fat options like pastrami, corned beef, or Italian meats. You can even ask to double the lean protein for an extra boost.
Go easy on the cheese: While most Firehouse subs come with provolone, Swiss, or Monterey Jack, cheese can add significant calories and saturated fat. Ask for a single slice or omit it entirely.
Pile on the veggies: This is where you can add volume, fiber, and nutrients without packing on calories. Ask for extra lettuce, tomatoes, onions, mushrooms, and bell peppers. This adds crunch and flavor, making the sandwich more filling.
Choose healthy condiments: Skip the standard mayo and opt for lighter, low-calorie toppings. Options like spicy mustard and pickles add flavor for minimal calories. Firehouse's deli mustard and light mayo are also suitable choices.

Comparison of Popular Firehouse Subs

To put the impact of your choices into perspective, here is a comparison of a healthy, custom-built sub versus some of the heavier menu items. Note: Nutritional information is based on a small sub unless otherwise specified.


Feature	Healthy Custom Sub	Engineer Sub (Small)	Steak & Cheese (Medium)	Smokehouse Brisket (Small)
Protein	Smoked Turkey (extra)	Smoked Turkey	Steak	Beef Brisket
Bread	Small Light Wheat	Small Wheat	Medium White	Small White
Cheese	Omit or Light	Swiss	Provolone	Cheddar
Calories	~300-350	350	820	450
Sodium	Lowered	1,150 mg	2,130 mg	1,600 mg
Fat	Low	18g	49g	25g

How to Create the Healthiest Meal Combination

Beyond the sandwich, Firehouse Subs offers other menu items that can complete a balanced meal. Choosing a healthy side instead of chips is a great way to improve your overall meal quality. The Firehouse Chopped Salad, particularly without meat, is a low-calorie option, while adding grilled chicken or ham can increase protein. A cup of chicken noodle soup is another comforting and lower-fat side option.

When ordering, remember that every modification matters. Requesting your sub 'light' or 'skinny' is not enough; be specific about your choices. For example, ask for 'no mayo' and 'extra lettuce and tomato'. While the chain’s emphasis on flavor and hearty portions may seem at odds with healthy eating, a few thoughtful choices make all the difference. For more detailed nutritional information and to build your custom sub, you can use the Firehouse Subs nutrition calculator.

Conclusion

While the small Engineer sub on wheat is often cited as the healthiest pre-made option, the truest healthiest sub at Firehouse is the one you customize yourself. By choosing a small, light wheat bun, a lean protein like smoked turkey or grilled chicken, and loading up on vegetables with minimal high-calorie sauces and cheeses, you can create a satisfying and nutritious meal. By taking control of your order, you can enjoy a fresh, delicious sub without derailing your diet.

Frequently Asked Questions

The lowest calorie pre-made option is often the small Engineer sub on wheat, especially if you ask for it with light mayo or no mayo. The lowest calorie sub you can make is a custom sub using the small light wheat roll, smoked turkey or grilled chicken, plenty of veggies, and light or no sauce.

The Veggie sub can be a healthy option, but you must be mindful of the portion size and toppings. The small version on wheat with light mayo and dressing will be much healthier than the medium or large with all standard toppings, as these can be surprisingly high in calories and sodium.

The light wheat roll is the best choice for a healthy sub, as it is lower in calories and sodium than the standard white bread. A gluten-free ciabatta roll is also available for those with dietary sensitivities.

Salads can be a healthy alternative, but it depends on the toppings. A Firehouse Chopped Salad with grilled chicken or ham is a good choice. However, some salads, like the Italian with Grilled Chicken, can have high sodium and fat content due to added salami.

To reduce sodium, choose the smallest sub size, opt for the wheat bun, select leaner meats like turkey or grilled chicken, and go easy on high-sodium condiments like certain cheeses and sauces. Customizing is key to reducing sodium levels.

Yes, you can. The best way to make a low-carb meal is to order a Firehouse Chopped Salad with a lean protein instead of a sub. Alternatively, you can ask for any sub's ingredients to be served on a salad bed instead of a bun.

The best healthy side choices include the Firehouse Chopped Salad (particularly without meat) or a cup of the Chicken Noodle Soup. Avoiding chips and mac and cheese is the best way to keep calories and fat low.