Fish Sauce in the UK: Where to Buy It and How to Choose the Right Bottle

The good news is that fish sauce is far easier to find in the UK than it was a decade ago. The slightly more complicated news is that not every bottle on a supermarket shelf is created equal, and the brand you grab matters more than most first-time buyers realise. This guide walks through exactly where to buy fish sauce in the UK, what supermarkets like Asda and Waitrose typically stock, how specialist grocers such as Longdan compare for range and authenticity, how to make sense of brands such as Squid and Three Crabs, and how fish sauce differs from soy sauce so you never reach for the wrong bottle again.

What Is Fish Sauce?

Fish sauce is a fermented condiment made primarily from anchovies, salt, and water, left to mature in barrels or earthenware jars for anywhere from several months to two years. The liquid that is pressed out during fermentation is fish sauce: amber to deep brown in colour, intensely salty, and loaded with the savoury depth that food scientists call umami.

What makes fish sauce different from most Western condiments is that it is rarely the star of a dish. It works in the background, rounding out soups, dipping sauces, marinades, and stir-fries the same way anchovy paste rounds out a Caesar dressing or Worcestershire sauce rounds out a Bolognese. Used well, you should not taste "fish" at all. You should taste a fuller, rounder version of whatever dish you are making.

How Fish Sauce Is Made

Fresh anchovies are layered with salt in large containers and left to ferment naturally, without added bacteria or starter cultures in traditional production. Over months of fermentation, enzymes break down the fish proteins into amino acids, which is where that signature umami flavour comes from. The first pressing, often called the "first draw," produces the highest-quality, most expensive fish sauce. Subsequent water-and-salt additions to the same fermenting fish produce lower grades used in cheaper blended products.

This is worth knowing because it explains why fish sauce prices vary so widely, from under three pounds for a small bottle of a mass-market blend to well over ten pounds for a premium, single-pressing bottle. Price is not just marketing. It usually reflects fermentation time and the proportion of fish protein actually used, which is exactly the kind of detail specialist grocers like

Fish Sauce vs Soy Sauce: What Is the Difference

Fish sauce and soy sauce are both fermented, salty, brown liquid condiments used across Asian cooking, which is exactly why people searching for "soy sauce fish sauce" or "fish sauce soy" often want to know whether the two are interchangeable. They are not, and understanding why will improve your cooking immediately.

Fish sauce is made from fermented fish, typically anchovies, and has a pronounced savoury, slightly funky, oceanic depth. It is used heavily in Vietnamese, Thai, and Filipino cooking.

Soy sauce is made from fermented soybeans, wheat, salt, and water, and has a more straightforward salty-savoury flavour without the marine undertone. It is the backbone of Chinese, Japanese, and Korean cooking.

Can You Substitute Soy Sauce for Fish Sauce

You can substitute soy sauce for fish sauce in a pinch, particularly if you need the dish to be vegetarian or vegan, but the flavour will shift noticeably. Soy sauce lacks the deep umami and slight sweetness that fish sauce contributes, so dishes like pho broth, nước chấm dipping sauce, or a Thai green curry will taste flatter and less complex. If you are substituting for dietary reasons rather than simply being out of stock, a combination of soy sauce with a small amount of seaweed or mushroom for extra umami gets you closer to the original flavour profile than soy sauce alone.

Where to Buy Fish Sauce in the UK

Fish sauce availability in the UK has improved considerably as Southeast Asian cuisine has become part of everyday cooking rather than a niche interest. That said, where you shop will significantly affect both the range of brands available and the price you pay per millilitre.

Fish Sauce at Asda

Asda stocks fish sauce within its Far Eastern sauces and ingredients section, typically alongside soy sauce and other Asian pantry staples. The most commonly available brand at Asda is Blue Dragon, a UK-distributed brand that produces a reasonably mild, accessible fish sauce aimed at home cooks who are not necessarily seeking an authentic Vietnamese or Thai profile.

Blue Dragon fish sauce at Asda generally comes in a 150ml bottle, making it a sensible entry point if you are trying fish sauce for the first time and do not want to commit to a large bottle before knowing how often you will use it. The price point is competitive, and availability through both in-store and online ordering makes it one of the most accessible options for UK shoppers who want fish sauce without a special trip to an Asian supermarket.

The trade-off is range. Asda's selection is functional rather than extensive, and you are unlikely to find Vietnamese-style brands like Squid or Three Crabs on a standard supermarket shelf. If you are cooking a specific regional dish and want an authentic, higher-protein fish sauce, Asda's offering is a reasonable backup rather than a destination, and it is worth comparing against what a specialist grocer like Longdan has in stock before settling.

Fish Sauce at Waitrose

Waitrose, given its broader international food range, tends to carry a slightly wider selection of Asian condiments than the average UK supermarket, though fish sauce specifically still sits within a fairly narrow band of recognisable, mainstream brands rather than specialist Vietnamese or Thai imports. Shoppers searching "fish sauce Waitrose" are often hoping for more authentic or premium options given the store's reputation for stocking higher-quality and specialist food products, and Waitrose does sometimes deliver on that within its World Foods aisle.

As with Asda, stock can vary by store size and location, so a flagship Waitrose branch in a major city is more likely to carry a broader range than a smaller local store. If you have a specific brand in mind, it is worth checking product availability online before making a special trip, or simply checking a specialist retailer like Longdan first, where stock tends to be more consistent precisely because Vietnamese and Southeast Asian groceries are the core business rather than a small section of a much larger store.

Fish Sauce at Longdan

Longdan stocks a noticeably wider range of fish sauce than most UK supermarkets, spanning both Vietnamese and Thai styles, so home cooks can match the bottle to the dish rather than settling for whatever single brand happens to be on a mainstream shelf. Bottles are typically labelled with clear nitrogen and ingredient information, making it easier to compare a milder, dipping-sauce-friendly option against a bolder, higher-protein variety meant for cooking into broths and marinades. Because fish sauce rarely gets used in isolation, Longdan's range sits alongside the rice vermicelli, rice paper, and other Vietnamese pantry staples that the same recipes call for, so a single order can cover everything from the seasoning to the noodles.

Why Supermarket Fish Sauce Selection Is Often Limited

UK supermarkets generally stock one or two fish sauce brands because fish sauce remains a relatively low-turnover product compared to staples like soy sauce or ketchup. Retailers allocate shelf space based on sales velocity, and a product used primarily by people cooking Southeast Asian food at home, rather than a broad mainstream audience, does not justify carrying five or six competing brands.

This is the same dynamic that affects rice noodles, rice paper, and other Vietnamese pantry staples in mainstream UK grocery stores: you will usually find one serviceable option, not the full spectrum of regional variation that exists within the category.

Specialist Asian Grocers: The Better Option for Authentic Flavour

As one of the UK's longest-established Vietnamese and Southeast Asian grocers, Longdan stocks a far deeper bench of fish sauce brands and the rice vermicelli, rice paper, and rice noodles that fish sauce-based dishes are typically built around, so shopping there for one ingredient often means leaving with everything else a recipe needs as well.

Popular Fish Sauce Brands Explained

Once you start looking beyond the supermarket shelf, you will encounter a handful of brand names repeatedly. Knowing what distinguishes them will help you choose the right bottle for what you are cooking, rather than picking blindly based on packaging.

Squid Brand Fish Sauce

Squid brand is a Thai-produced fish sauce known for a notably strong, assertive flavour and aroma. It is harvested relatively early in the fermentation process, which gives it a bolder, more pungent character compared to lighter styles. Cooks who want fish sauce to genuinely register in a finished dish, particularly in stir-fries, marinades, and heartier soups, often reach for Squid brand because a small amount delivers a noticeable depth of flavour. It is less commonly used as a straight dipping sauce on its own, given its intensity, and works better diluted or balanced with sugar, lime, and chilli in a nước chấm-style preparation. It is also one of the brands more commonly found at specialist grocers such as Longdan than on a typical UK supermarket shelf.

Three Crabs Fish Sauce

Three Crabs is one of the most recognisable fish sauce brands internationally and is often the entry point for home cooks new to the ingredient. It has a lighter, sweeter, more delicate flavour profile than Squid brand, the result of a longer fermentation process that produces a paler colour and gentler taste. This makes it more forgiving for first-time use and well suited to dipping sauces where you want fish sauce to blend smoothly with lime juice, sugar, garlic, and chilli rather than dominate the bowl. Because it is milder, some experienced cooks find it slightly less robust for deep, savoury cooking applications compared to bolder Vietnamese or Thai brands, though it remains a reliable, widely available choice.

Longdan Fish Sauce

Longdan's fish sauce, labelled as a product of Vietnam, is formulated as a ready-to-use dipping sauce rather than a pure, unblended fish sauce. According to the ingredient list, fermented fish sauce (anchovy, salt, water) makes up only 18.75% of the bottle, with water and sugar forming the bulk of the product at over 75% combined, alongside garlic, chilli, rice vinegar, a small amount of flavour enhancer, and a preservative. This puts it closer in style to a pre-mixed nước chấm than to a concentrated cooking fish sauce like Three Crabs or Squid brand. It suits the same use case Three Crabs is known for, an approachable, ready-balanced dipping sauce for spring rolls, grilled meats, and rice dishes, since the sweetness, acidity, and chilli are already built in rather than left for the cook to adjust. It is not the right choice for recipes calling for concentrated fish sauce as a cooking ingredient, such as pho broth or a stir-fry marinade, where the added sugar and dilution would throw off the balance of the dish.

How to Read a Fish Sauce Label

The single most useful piece of information on a fish sauce label, beyond the ingredients list, is the protein or nitrogen content, often expressed in degrees N on traditional Vietnamese and Thai bottles. A higher nitrogen reading generally indicates a higher concentration of fish protein and a first-pressing product, which correlates with better flavour and quality. Bottles without this measurement, or with very low readings, are typically diluted, blended products using water and salt additions to extend a smaller batch of original fermented liquid.

Checking the ingredients list is equally important. A traditional fish sauce should list anchovy, salt, and water as the primary or only ingredients. Products with added sugar, hydrolysed vegetable protein, or preservatives further down the list are usually mass-market blends designed for accessibility and shelf stability rather than authenticity, which is not necessarily a bad thing for casual cooking, but worth knowing if you are seeking a closer-to-traditional flavour. Specialist grocers such as Longdan tend to list nitrogen content and ingredients more transparently on product pages than mainstream supermarket listings, which makes this kind of comparison shopping considerably easier.

How to Choose the Right Fish Sauce for Your Cooking

The right bottle depends on how you intend to use it, and matching the fish sauce to the application makes a measurable difference in the finished dish.

For Dipping Sauces

If you are primarily making nước chấm, the Vietnamese dipping sauce served with spring rolls, grilled meats, and rice dishes, a lighter, slightly sweeter fish sauce such as Three Crabs works well because it balances smoothly with lime juice, sugar, garlic, and chilli without overwhelming the other flavours. The goal in a dipping sauce is harmony between sweet, sour, salty, and savoury, so a milder base gives you more control over that balance. If you are also making fresh spring rolls to go alongside, a specialist grocer like Longdan is a convenient single stop for the fish sauce, rice paper, and vermicelli the dish needs. (Internal link opportunity: link "rice paper" to your Longdan rice paper category page.)

For Cooking Into Dishes

When fish sauce is going into a broth, marinade, stir-fry, or braise where it needs to hold its own against other strong flavours, a bolder option such as Squid brand or a higher-nitrogen Vietnamese fish sauce delivers more depth. Heat and other ingredients will mellow the intensity, so starting with a more concentrated, characterful fish sauce generally produces a richer final result than relying on a milder, more diluted product and trying to compensate with quantity.

For First-Time Buyers

If you are buying fish sauce for the first time and unsure how often you will use it, starting with a smaller bottle from a recognisable brand, whether that is what you find at Asda or Waitrose, or a small bottle from a specialist grocer such as Longdan, is a sensible way to get comfortable with the ingredient before investing in a larger, premium bottle. Fish sauce has a long shelf life once opened, typically a year or more stored in a cool, dark place, so there is little risk in buying a bottle and using it gradually as your familiarity with Southeast Asian cooking grows.

Frequently Asked Questions

Is fish sauce the same as soy sauce?

No. Fish sauce is fermented from anchovies and has a deep, savoury, slightly oceanic flavour, while soy sauce is fermented from soybeans and has a more straightforward salty profile without the marine character. They are used in different cuisines and are not direct substitutes for each other in most recipes.

Can I substitute soy sauce for fish sauce?

You can in an emergency or for dietary reasons, but the dish will taste noticeably different and less complex. Fish sauce contributes umami depth that soy sauce alone does not replicate, so use this substitution only when fish sauce is genuinely unavailable.

Does Waitrose sell Vietnamese fish sauce?

Waitrose typically stocks mainstream fish sauce brands within its World Foods aisle rather than a wide range of specialist Vietnamese imports. For authentic Vietnamese fish sauce with higher protein content, a specialist Asian grocer such as Longdan is more likely to carry the brands and quality level Vietnamese home cooks use.

What is the best fish sauce brand for Vietnamese cooking?

There is no single "best" brand, since the right choice depends on the dish. For dipping sauces, a lighter, sweeter style such as Three Crabs works well. For cooking into broths, marinades, and stir-fries, a bolder, higher-nitrogen Vietnamese-style fish sauce delivers more depth. Checking the nitrogen content and ingredients list on the label is the most reliable way to judge quality regardless of brand.

How do I store fish sauce after opening?

Fish sauce does not require refrigeration, though storing it in a cool, dark cupboard away from direct heat and sunlight will preserve its flavour for longer. Most opened bottles remain good for a year or more thanks to the high salt content, which naturally inhibits spoilage.

Conclusion

Fish sauce is one of those ingredients that rewards a little bit of label-reading and brand awareness far more than most condiments do. If convenience is the priority, fish sauce at Asda or Waitrose will get a basic recipe over the line, particularly with accessible brands like Blue Dragon readily available in mainstream UK supermarkets. But if you are cooking Vietnamese or Thai food regularly and want the depth of flavour that authentic recipes are built around, it is worth seeking out a specialist Asian grocer for a wider range of brands, including Squid and Three Crabs, along with higher-protein, traditionally produced options that supermarket shelves rarely stock. Longdan is one of the most reliable places in the UK to find that range, alongside the rice vermicelli, rice paper, and broader Vietnamese pantry staples that fish sauce is so often cooked alongside.

Understanding the difference between fish sauce and soy sauce, knowing how to read a nitrogen rating on a label, and matching the right style of fish sauce to dipping sauces versus cooked dishes will do more for your cooking than any single brand recommendation. Once you know what you are looking for, finding fish sauce in the UK, whether at a supermarket or a specialist grocer, becomes a much simpler decision.