Vietnam farms clams and mollusks across more than 41,500 hectares of coastal waters, producing roughly 265,000 tons a year — clams alone account for about 179,000 tons of that, according to the Vietnam Association of Seafood Exporters and Producers (VASEP). That scale is why clams have become Vietnam's leading shellfish export by value. But buyers who source clams the way they source shrimp or pangasius — by species and size grade alone — usually end up with a spec that doesn't match what the factory actually ships.
Two species carry almost all the volume
The workhorse is Meretrix lyrata, the white (or "lyrate") hard clam farmed intensively on the tidal flats of Ben Tre and neighboring Mekong Delta provinces — this is the species most buyers mean when they simply ask for "Vietnamese clam." Alongside it, factories also process a brown clam (often locally labeled by shell color rather than a single scientific name across suppliers, so I always confirm the species with a photo and a Latin name on the factory's own spec sheet before booking). White and brown clam are priced and graded separately, and mixing them into one line item on a PO is one of the more common reasons buyers get short-shipped on the grade they actually wanted.
Grading runs on pieces-per-kilogram, not "small/medium/large"
This is the detail that trips up buyers new to the category: clam size is specified as a count range — for example 40/60, 60/80, 100/120, or 120/150 — meaning that many individual clams make up one kilogram. A 40/60 clam is large and meaty; a 120/150 clam is small, and priced accordingly lower per kilogram even though the per-piece yield is what actually matters to a foodservice buyer plating individual portions. Per VASEP's market reporting on EU shipments, frozen boiled white clam in the 100/120 count has traded in the roughly $1.30–1.43/kg range into Portugal, Spain, and Italy, while the smaller-count, higher-value 40/60 boiled brown clam has run closer to $1.45–2.50/kg depending on destination market and season — a reminder that count size, not just species, is what moves the price. Always request the count range in writing, not just "large" or "small," and ask the factory to state whether the count is measured pre- or post-cook, since boiling changes both weight and shell-open rate.
Boiled, raw, whole-shell, or meat — pick one and put it in the spec
Most of Vietnam's clam exports to the EU move as frozen boiled product — either whole-in-shell (open shell, meat visible) or picked meat — because boiling is both a food-safety step and a practical way to sort dead or unopened clams out of the pack before freezing. Raw frozen whole clam exists but is a smaller, more logistically demanding category since live/raw shellfish carries tighter cold-chain and health-certificate requirements. If your recipe needs raw clam meat for a specific texture, say so explicitly — a factory quoting on "clam" alone will usually default to the boiled spec because it's what they run at volume.
Oysters are a smaller, different supply chain
Oysters are a much smaller export line than clams and follow a different pattern. Vietnam farms two main species — the Portuguese oyster (Crassostrea angulata), the broadly farmed commercial species, and the Pacific oyster (Crassostrea gigas), grown mainly around Quang Ninh in the north and Ba Ria–Vung Tau in the south. Unlike clams, most of Vietnam's oyster export volume moves chilled and fresh rather than frozen, and it is heavily concentrated toward a small number of nearby markets that can absorb a short-shelf-life product — buyers further afield should ask directly whether a factory has a frozen or IQF oyster meat line, since not every clam exporter also runs oyster, and not every oyster farm is set up for frozen export at all.
What this means for your buying spec
Before you send a PO, confirm four things in writing: the species (Latin name, not just "white clam" or "oyster"), the count-per-kilogram range and whether it's measured before or after cooking, whether the product is boiled or raw and whole-shell or meat-only, and — for EU-bound shipments — that the factory is on the current EU-approved establishment list for bivalve molluscs, since that approval is granted per facility, not per product category, and lapses do happen. A supplier who answers all four without hesitation is telling you something useful about how carefully they run their own line, independent of the price they quote.
Sourcing clam and oyster from Vietnam?
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