Parents packing regular school lunches
Compare tin sizes, ingredients and instructions for storing leftovers when tuna appears regularly in sandwiches or salads.
Who is this for?
Shoppers seeking certified tuna
If MSC certification is the deciding factor, check the blue ecolabel on the particular tin or multipack, not just the brand’s wider sourcing policy.
Families checking allergens and school rules
Tuna contains fish. Check the current pack information, the pupil’s medical plan where relevant and the school’s own food policy before packing it.
What to check before buying
Start with the certification you require, then choose a filling medium and pack size that work for the lunch and any leftovers.
| Priority | What to check | Your needs |
|---|---|---|
| MSC certification | Look for the blue MSC ecolabel on the exact tin or multipack. Treat a brand sourcing statement or catch-method claim as a separate piece of information. | I want an MSC-certified option rather than relying on general sustainability wording. |
| Filling medium | Read the ingredients and nutrition panel for the particular spring-water, brine or oil product. Compare values on the same stated basis, such as per 100g drained. | For this sandwich or salad, I’d choose a filling medium that suits the recipe and check the label if I want to avoid added oil. |
| Fish allergen | Check the current ingredient and allergen information when choosing or changing products. Follow the pupil’s medical plan and the school’s food policy where applicable. | If a pupil has a fish allergy, I need to establish whether tuna can be included before preparing the lunch. |
| Pack size and leftovers | Compare the amount in each tin with the lunches you plan to make. Read that product’s instructions for storing and using any remainder. | A multipack may suit repeated lunches, but I still need a plan for an opened tin. |
| Variety of fish | Consider tuna alongside other fish choices. The NHS says fresh and canned tuna do not count as oily fish. | If tuna appears often in packed lunches, I don’t want to mistake it for an oily-fish option. |
Common buying mistakes
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Assuming a sourcing commitment certifies every pack
Brand policies do not replace a product-level label. In its February 2026 UK review, the Marine Stewardship Council found the blue MSC ecolabel on 138 of 271 shelf-stable tuna products.
Check the exact tin or multipack for the blue MSC ecolabel when that certification matters to you.
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Treating pole-and-line caught as an MSC label
M&S describes its canned tuna as pole-and-line caught. That catch-method statement and MSC certification answer different questions.
Use the catch-method information if it is your criterion; if you also require MSC certification, check the chosen pack for the ecolabel.
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Overlooking the fish allergen
Tuna is fish, which the Food Standards Agency identifies among the allergens to consider. A school lunch needs particular care where a pupil has a fish allergy.
Read the current pack information and follow the pupil’s medical plan and the school’s food policy.
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Opening more tuna than the lunch needs
Storage instructions apply once a tin is opened. For its spring-water tuna steak, M&S instructs customers to move unused contents to a non-metallic container, refrigerate them and eat them within two days.
Choose a tin size that fits your plans and follow the instructions on the product you buy.
Brand and retailer references
Princes
Princes says it has completed its commitment for 100% of its tuna to be MSC certified.
- Its spring-water tuna chunks list tuna and spring water as ingredients, with 23.5g protein per 100g drained, according to Princes.
- Check the MSC mark, filling medium and ingredients on the individual product you choose.
John West
A Tesco Groceries listing identifies a John West No Drain Tuna Chunks with a Little Brine MSC 3x100g product.
- The listed No Drain format is worth considering if you want less preparation when making lunch.
- That listing does not establish the MSC status or ingredients of every John West product; check the chosen pack.
Tesco
The Marine Stewardship Council listed Tesco among supermarkets carrying certified tuna products in its analysis of the 2023/24 UK market.
- Tesco Groceries lists both branded and own-brand tinned tuna.
- A retailer’s inclusion in the analysis does not certify each own-brand tin; inspect the exact pack.
Sainsbury's
The Marine Stewardship Council’s 2025 UK market analysis described Sainsbury's as offering 100% MSC-labelled canned tuna in its 2023/24 coverage.
- That analysis provides a historical reference for shoppers comparing retailer sourcing.
- Check the current label and product details on the tin you intend to buy.
Asda
The Marine Stewardship Council listed Asda among supermarkets carrying certified tuna products in its analysis of the 2023/24 UK market.
- The analysis identifies Asda as a retailer where certified tuna was represented.
- It does not establish certification for every Asda or branded tuna product sold there.
M&S
M&S says its canned tuna is pole-and-line caught and describes its seafood sourcing standard.
- Its spring-water tuna steak information identifies skipjack tuna and spring water as ingredients and gives instructions for storing leftovers.
- Its catch-method and sourcing statements are not proof of an MSC ecolabel on a particular tin.
Joybuy tuna options
These Princes multipacks offer sunflower-oil and brine fillings for packed-lunch planning. If MSC certification is essential, check the blue ecolabel on the exact pack before choosing either one.
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Princes Tuna Chunks in Sunflower Oil, 4 x 145g
Consider the sunflower-oil filling for a sandwich or salad recipe where added oil suits your plans.
The pack contains four 145g tins. Tuna contains fish; check the current allergen information and the exact pack’s MSC label if certification is required.
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Princes Tuna Chunks in Brine, 4 x 145g x 12 packs
Consider the brine filling if it suits the lunches you prepare, and check that the bundle quantity fits your household’s plans.
The stated format is 12 packs of four 145g tins. Tuna contains fish; check the current allergen information and the exact pack’s MSC label if certification is required.
Frequently asked questions
How can I identify MSC-certified tinned tuna?
Look for the blue MSC ecolabel on the exact tin or multipack. A brand’s sourcing statement is not a substitute for checking the product: in its February 2026 UK review, the Marine Stewardship Council found the label on 51% of shelf-stable tuna products, or 138 of 271 products.
When does tuna in spring water make sense for a packed lunch?
It is an option when you want tuna without added oil. Princes lists tuna and spring water as the ingredients of its spring-water chunks; compare the ingredients, salt values and filling medium on the exact products you are considering.
Does canned tuna count as oily fish?
No. The NHS says fresh and canned tuna do not count as oily fish, so tuna does not fulfil the oily-fish part of its general guidance on eating a variety of fish.
What should I do with tuna left after opening a tin?
Follow the instructions on the tin you opened. For its spring-water tuna steak, M&S says to move unused contents to a non-metallic container, refrigerate them and eat them within two days; check a different product’s label for its own directions.