Tuna Mayo and Cheese Spud: calories and sugar by portion and age

Subway Tuna Mayo and Cheese Spud, jacket potato with butter, melted cheese and tuna mayo on white paper, nutrition and calories

Boone’s analysis puts Subway Tuna Mayo and Cheese Spud at 28% of an adult’s daily calories, 53% of the daily salt limit for a child aged 4 to 6 and 0.8 teaspoons of free sugar.

How many calories are in a Subway Tuna Mayo and Cheese Spud? It contains 558 kcal, 27g of fat (11g saturated), 3g of sugar and 1.6g of salt.

Build a full meal with our nutrition calculator

Use the Boone meal calculator to build a full meal rather than view this item on its own. Add a sub, a side, a cookie, cheese or a sauce, then choose your age and sex for a more accurate view of how a Tuna Mayo and Cheese Spud fits into a day.

Nutrition information

Nutrition information: Subway Tuna Mayo and Cheese Spud

Energy	558 kcal
Fat	27g
of which saturates	11g
Carbohydrate	54g
of which sugars	3g
Fibre	7.4g
Protein	26g
Salt	1.6g

Nutrition figures are Subway UK and ROI published data (September 2026), per item as sold. Boone converts them to the portion and age comparisons on this page.

Subway Tuna Mayo and Cheese Spud contains 558 kcal, which is 28% of the 2,000 kcal adult daily reference intake. It provides 27g of total fat, of which 11g is saturated, 3g of sugar, 1.6g of salt and 26g of protein.

The saturated fat content of 11g represents 55% of the adult daily guideline of 20g. It also provides 7.4g of fibre, 25% of the 30g adult daily recommendation.

Subway gives the portion weight as 398g, which works out at 140 kcal per 100g.

Sugar in Subway Tuna Mayo and Cheese Spud

Subway Tuna Mayo and Cheese Spud contains 3g of free sugar per standard serving (0.8 teaspoons). Subway publishes a total sugar figure of 3g and Boone counts all of it as free sugar. Moderate sugar

The NHS free sugar limit is 30g per day for adults, 24g for children aged 7 to 10, and 19g for children aged 4 to 6. Free sugar excludes the sugars naturally present in milk and whole fruit and vegetables.

Free sugar by portion: Subway Tuna Mayo and Cheese Spud

Portion	Adult (female) 30g	Adult (male) 30g	Age 11 to 17 30g	Age 7 to 10 24g	Age 4 to 6 19g
Per portion	3g 10%	3g 10%	3g 10%	3g 13%	3g 16%

Teaspoons: 0.8 tsp

Boone calculates these percentages from Subway UK published nutrition data against UK Dietary Reference Values and NHS free sugar and salt limits. Free sugar, salt, calories and saturated fat are limits to stay under. For guidance only.

Salt in Subway Tuna Mayo and Cheese Spud

Subway Tuna Mayo and Cheese Spud contains 1.6g of salt per standard serving. Moderate salt

Children have lower salt limits: 3g per day for ages 4 to 6, 5g for ages 7 to 10.

Salt by portion: Subway Tuna Mayo and Cheese Spud

Portion	Adult (female) 6g	Adult (male) 6g	Age 11 to 17 6g	Age 7 to 10 5g	Age 4 to 6 3g
Per portion	1.6g 27%	1.6g 27%	1.6g 27%	1.6g 32%	1.6g 53%

Calories in Subway Tuna Mayo and Cheese Spud

Subway Tuna Mayo and Cheese Spud contains 558 kcal per standard serving. Moderate calorie share

Daily calorie needs vary by age and sex.

Calories by portion: Subway Tuna Mayo and Cheese Spud

Portion	Adult (female) 2000 kcal	Adult (male) 2500 kcal	Age 11 to 17 1936 kcal	Age 7 to 10 1553 kcal	Age 4 to 6 1291 kcal
Per portion	558 kcal 28%	558 kcal 22%	558 kcal 29%	558 kcal 36%	558 kcal 43%

Saturated fat in Subway Tuna Mayo and Cheese Spud

Subway Tuna Mayo and Cheese Spud contains 11g of saturated fat per standard serving. High saturated fat

The saturated fat guideline is 20g a day for women and 30g for men, and lower for children.

Saturated fat by portion: Subway Tuna Mayo and Cheese Spud

Portion	Adult (female) 20g	Adult (male) 30g	Age 11 to 17 20g	Age 7 to 10 18g	Age 4 to 6 16g
Per portion	11g 55%	11g 37%	11g 55%	11g 61%	11g 69%

Free sugar vs total sugar

Where the sugar comes from: Subway Tuna Mayo and Cheese Spud

All 3g counts as free sugar. Boone makes no deduction for milk or whole fruit in this item. That is 0.8 teaspoons.

NHS daily free sugar limits: 30g for adults and children 11+, 24g age 7 to 10, 19g age 4 to 6.

Ultra-processed food: what is really in it

Processing: Subway Tuna Mayo and Cheese Spud

Boone cannot classify this item, because Subway does not publish an ingredient list for it.

NOVA classification is read from an ingredient list. Without one there is no way to count additives, separate raw ingredients from manufactured ones, or say whether an item is ultra-processed. Boone does not estimate a NOVA group, because a guess presented as a classification would be worse than saying nothing.

Ingredients

Subway does not publish an ingredient list for this item

Ingredients: Subway Tuna Mayo and Cheese Spud

Subway’s September 2026 UK nutrition and allergen guides do not include an ingredient list for a Subway Tuna Mayo and Cheese Spud, and it is under no legal obligation to provide one.

Food made to order in a restaurant counts as non-prepacked under UK food law. The legal requirement is to declare the 14 major allergens, and for large businesses in England to show calories at the point of choice. A full ingredient list is voluntary.

Without one, no page on this site can tell you how many ingredients are in this item, how many of them are manufactured substances, or whether it is ultra-processed. Boone will not estimate any of it.

Subway publishes allergen information for each ingredient, and Boone uses it to build the allergen table below. Recipes change, so always check in restaurant before ordering if you have an allergy.

Allergens at a glance

Subway Tuna Mayo and Cheese Spud contains milk, eggs, fish and mustard.

Allergen information: Subway Tuna Mayo and Cheese Spud

Allergen	Status
Wheat	Not present
Rye	Not present
Barley	Not present
Oats	Not present
Spelt	Not present
Sesame	Not present
Soya	Not present
Milk	Contains
Eggs	Contains
Fish	Contains
Crustaceans	Not present
Molluscs	Not present
Peanuts	Not present
Tree nuts	Not present
Celery	Not present
Mustard	Contains
Lupin	Not present
Sulphites	Not present

Contains = declared as an ingredient. May contain traces = Subway’s suppliers say the allergen is present at the manufacturing site and there is a significant risk of cross-contamination. Subway publishes allergens by ingredient, not by finished item, so Boone builds this table from the jacket potato and its toppings. Food is freshly prepared in Subway kitchens where many allergens are handled, so Subway cannot guarantee any item is allergen free. Vegan items are made to vegan recipes but are not suitable for people with milk or egg allergies.

Frequently asked questions

How many calories are in a Subway Tuna Mayo and Cheese Spud?+

Boone calculates that a Subway Tuna Mayo and Cheese Spud contains 558 kcal, which is 28% of an adult’s 2,000 kcal daily reference intake and 43% of the daily intake for a child aged 4 to 6.

How much sugar is in a Subway Tuna Mayo and Cheese Spud?+

A Subway Tuna Mayo and Cheese Spud contains 3g of sugar, all of which counts as free sugar, or about 0.8 teaspoons. That is 10% of an adult’s 30g daily limit and 16% of the 19g limit for a child aged 4 to 6.

How much saturated fat is in a Subway Tuna Mayo and Cheese Spud?+

A Subway Tuna Mayo and Cheese Spud contains 11g of saturated fat. Boone calculates this as 55% of the daily guideline for an adult woman and 37% for an adult man, because the guideline differs by sex: 20g and 30g.

How much salt is in a Subway Tuna Mayo and Cheese Spud?+

A Subway Tuna Mayo and Cheese Spud contains 1.6g of salt. Boone calculates that as 53% of the daily limit for a child aged 4 to 6 and 27% of an adult’s 6g limit.

Is a Subway Tuna Mayo and Cheese Spud ultra-processed?+

Subway does not publish ingredient lists for food made to order, and UK law does not require it to, so Boone cannot assign a NOVA group to this item.

Is a Subway Tuna Mayo and Cheese Spud classed as less healthy?+

Under the government’s 2018 nutrient profiling model a Subway Tuna Mayo and Cheese Spud scores -2. The model classes a food scoring 4 or more as less healthy, so this item would not be. The 2018 model is published but not yet used for advertising rules. Subway publishes fibre, so Boone uses its figure.