Who may find this useful

Shoppers comparing salt labels

If reducing salt is your priority, compare the nutrition information for the exact tin rather than treating “in spring water” as a shortcut.

Online-basket meal planners

For salads, sandwiches, pasta or jacket potatoes, tin size and drained quantity help you choose an amount you will use. Check the opening and storage instructions as well.

Shoppers checking sourcing information

If fishing-method or certification statements affect your choice, look for them on the specific product listing alongside its nutrition panel.

What to check when buying

Start with salt on the exact product label, then choose a pack size that fits how much tuna you use and how you store leftovers.

Concern What to check Who this matters to
Salt content Compare salt per 100g drained across tins, then check the stated serving figure for the amount you expect to eat. If I am choosing tuna primarily to reduce salt, the liquid it comes in is not enough to decide; I need the exact tin’s nutrition panel. About 42% of consumers put that verified salt comparison first.
Pack planning Compare tin count and drained weight, rather than relying on the total pack weight alone. When I am adding tuna for several meals, I want a pack that supplies an amount I will use. For about 25% of consumers, matching the pack to those meals is the primary concern.
Portions and leftovers Check the drained amount per tin and the product’s after-opening storage instructions. If I usually need tuna for one lunch, an opened tin may leave more than I want to store. Portion convenience comes first for about 17% of consumers.
Sourcing information Look for certification or fishing-method statements on the exact product, without treating them as salt claims. I may want stated sourcing information to settle a choice between tins that otherwise meet my needs. About 16% of consumers make that their primary concern.

Common mistakes with online tuna listings

  • Assuming spring water means reduced salt

    Spring-water tuna in the Sainsbury’s, Tesco, Asda, M&S and John West listings considered here has differing salt values, from 0.12g to 0.90g per 100g drained.

    Compare the drained per-100g figure for the exact product before using its serving figure to assess the amount you plan to eat.

  • Comparing pack weight without checking drained weight

    Water-packed tins can contain different amounts of drained tuna, even when their pack weights look similar.

    Check the drained weight per tin and the number of tins before deciding whether the pack fits your meals.

  • Assuming every opened tin has the same storage window

    The storage instructions on the product listings considered here differ. A tin size that leaves unused tuna makes those instructions more relevant.

    Follow the label on the delivered pack for transferring, refrigerating and using leftovers.

  • Reading a sourcing statement as a salt claim

    MSC certification or a pole-and-line statement describes sourcing, not the salt value on the nutrition panel.

    Check salt separately, and apply any sourcing statement only to the product on which it appears.

Brands to compare by product

These figures describe the named spring-water products, not every tuna tin sold under each brand.

Sainsbury’s

Sainsbury’s lists 0.12g salt per 100g drained and 0.06g per half-can serving for its Tuna Chunks in Spring Water 4x145g.

  • The listing also states pole-and-line sourcing and MSC certification for this product.
  • Recheck the delivered pack’s label; this salt figure does not apply to every Sainsbury’s tuna product.

M&S

M&S lists 0.75g salt per 100g for its Tuna Chunks in Spring Water.

  • Its listing provides pole-and-line and Forever Fish sourcing information.
  • The stated salt value is higher than the 0.12g per 100g drained on the named Sainsbury’s product; check the exact pack’s measurement basis when comparing.

John West

Asda lists 0.80g salt per 100g drained for John West Tuna Chunks in Spring Water 4x125g.

  • The Asda listing describes easy-open packaging.
  • Check that this pack size and its after-opening storage instructions suit how you use it.

Princes

Sainsbury’s lists 0.90g salt per 100g drained for its Princes spring-water tuna chunks 4x145g listing.

  • The Princes product information includes an MSC certification statement.
  • Do not transfer a salt figure from one Princes listing or pack format to another; check the product in your basket.

Tesco

Tesco lists 0.90g salt per 100g drained and 0.50g per 56g drained can for its Tuna Chunks in Spring Water 3x80g.

  • The stated drained amount per can helps with portion planning.
  • A smaller can does not itself establish a lower salt concentration.

Asda

Asda lists 0.90g salt per 100g drained and 0.46g per half-can serving for its Tuna Chunks in Spring Water 4x145g.

  • The listing includes an MSC certification statement for this product.
  • Compare its drained per-100g salt figure with other tins before using the smaller serving figure to make a choice.

A Joybuy spring-water tuna option

For a spring-water tuna option in an online basket, check this product’s pack label before treating it as a reduced-salt choice. Its listed salt figure does not specify whether the 100g amount is drained.

Topical Sun Tuna Chunks in Springwater 160g

Topical Sun Tuna Chunks in Springwater 160g

Consider this spring-water tin if its portion suits your planned meals, but check the pack’s salt per 100g drained and per-serving figures before comparing it with the tins above.

The title says 160g, while the accompanying product information says 80g net quantity. Confirm the pack quantity before ordering, and check the packaging for fish, soybean and wheat allergen information if relevant.

View on Joybuy

Questions about salt, portions and storage

Does tuna in spring water have less salt?

Not necessarily. The named spring-water products on Sainsbury’s, Tesco, Asda, M&S and John West listings show different salt values, so compare the exact tin’s nutrition panel rather than its packing liquid.

How do I compare tins of different sizes?

Compare salt per 100g drained first, then look at salt per stated serving for the amount you expect to eat. Tesco, for example, lists both a per-100g drained value and a value for its 56g drained can.

What should I do with tuna left after opening?

Follow the instructions on the delivered product. The listings considered here commonly call for transferring leftovers to a non-metallic container and refrigerating them, but the period for using them differs by product.

What if fish allergens matter to my household?

Tuna is fish, and the named product listings identify fish as an allergen. Read the exact product’s ingredient and allergen information and check the delivered pack, particularly if a substitution is made.

Does a sourcing statement tell me anything about salt?

No. An MSC or pole-and-line statement concerns sourcing; use the nutrition panel to assess salt. Check that any sourcing statement applies to the particular tin and variant you are ordering.