Is seafood kosher? The answer depends entirely on what kind of seafood you’re asking about. Fish with both fins and easily removable scales are considered kosher under Jewish dietary law. Shellfish, crustaceans, and cephalopods like squid and octopus are not. The Torah lays out this rule in Leviticus 11:9-12, and it’s the foundation of how kashrut treats every aquatic creature. You can look up any fish at KosherFish.co and get the kosher verdict in seconds.
What Makes Seafood Kosher? The Kashrut Rules
Kashrut, the system of Jewish dietary laws, draws a clear line between kosher and non-kosher seafood. According to the Torah, a water creature is considered kosher only if it meets two specific requirements: it must have fins and it must have scales that can be removed without tearing the skin. Both conditions must be present. A creature that has one but not the other doesn’t qualify.
Leviticus 11:9-12 states: “These you may eat of all that are in the waters: everything in the waters that has fins and scales… but anything in the seas or rivers that does not have fins and scales… is forbidden to you.” Deuteronomy 14:9-10 repeats the same requirements. According to Jewish law, these two verses are the entire basis for determining whether any seafood is kosher or forbidden.
Not all scales qualify under this interpretation. The halachic requirements specify scales that can be peeled off cleanly. The two scale types that meet this standard are cycloid scales (smooth, round-edged) and ctenoid scales (comb-edged). Both lift off without tearing. Fish like salmon, tuna, tilapia, and halibut all have these qualifying scales and are considered kosher. They are among the most popular kosher-approved foods in Jewish households.
Scales that do not qualify include ganoid scales (found on sturgeon) and placoid scales (found on sharks). Ganoid scales are embedded in the skin and cannot be removed cleanly. Placoid scales are actually dermal denticles, tiny tooth-like structures, not true scales in the halachic sense. Both disqualify the fish, which is why sturgeon and shark are not considered kosher, even though biologists classify them as having some form of scale covering. Catfish has no scales at all, which is why it’s forbidden under Jewish law.
The Orthodox Union (OU) and the Chicago Rabbinical Council (cRc) both publish kosher fish lists based on these requirements. According to both agencies, the rule applies to all water creatures: if it doesn’t have fins and removable scales, it’s not considered kosher for consumption. There is no disagreement between major kosher authorities on this basic standard.
Which Seafood Is Considered Kosher?
Any finfish with qualifying scales is considered kosher. While the full KosherFish database covers 291 such species, most of what you’ll find at a market or restaurant falls into a few well-known categories. Here are the most commonly eaten kosher seafood options:
- Salmon: cycloid scales, confirmed kosher by the OU and cRc. One of the most popular kosher fish for Shabbat and holiday meals.
- Tuna: ctenoid scales, confirmed kosher. Available fresh, canned, and frozen (certified canned tuna is widely available).
- Tilapia: cycloid scales, confirmed kosher. Mild flavor, widely available, and among the most affordable kosher fish.
- Halibut: ctenoid scales, confirmed kosher. Firm white fish, used in both traditional and contemporary Jewish cooking.
- Cod and haddock: both have qualifying scales and are confirmed kosher. “Scrod” sold at markets is typically young cod or haddock, both kosher.
- Mahi-mahi: ctenoid scales, confirmed kosher by the OU.
- Flounder and sole: ctenoid scales, both considered kosher.
- Sardines, herring, and mackerel: cycloid or ctenoid scales, all confirmed kosher. Herring is particularly traditional in Ashkenazic cooking.
- Trout (rainbow trout, brook trout): cycloid scales, confirmed kosher.
Bass varieties and kosher status. Bass is a broad category and most bass species are considered kosher. Striped bass has cycloid scales and is confirmed kosher by the cRc. Largemouth bass, smallmouth bass, rock bass, white bass, yellow bass, spotted bass, and black bass all have qualifying scales. While different bass species vary in flavor and texture, they share the same basic kosher status: fins and removable scales present, considered kosher. Black sea bass and white sea bass are also considered kosher. If you’re buying bass at a market, confirm the species, since the name “bass” is applied to many different fish. Chilean sea bass is actually Patagonian toothfish and is considered kosher by the cRc, though its sustainability record is separate from its religious status.
Fresh whole fish with skin and scales intact is the easiest kosher seafood to buy without certification. When you can see the scales and identify the species, you can confirm it’s considered kosher. According to the cRc, whole fresh kosher fish generally doesn’t need a hechsher in this form. That changes once the fish is processed and scales are removed.
Which Seafood Is Forbidden Under Jewish Law?
A large portion of what people call seafood is forbidden under Jewish dietary law. These non-kosher creatures fail the Torah’s two-part test for one or both reasons: no fins, no qualifying scales, or both.
Shellfish are forbidden. Shrimp, lobster, crab, clams, oysters, mussels, and scallops all lack fins and qualifying scales. The Torah explicitly forbids water creatures without fins and scales (Leviticus 11:12), and the OU and cRc both list these shellfish as not kosher. No mainstream Orthodox authority permits them. They are among the most frequently asked-about non-kosher foods because they appear on so many restaurant menus.
Cephalopods are not kosher. Squid (calamari), octopus, and cuttlefish have no fins and no scales. According to Jewish law, these creatures are forbidden for consumption, just as shellfish are. The OU lists squid and octopus as non-kosher.
Certain fish are not considered kosher because of their scale type. Shark has placoid scales (dermal denticles) that don’t meet the halachic definition. Catfish has no scales at all, making it a non-kosher fish that is explicitly forbidden. Eel lacks qualifying fins and scales. Sturgeon, despite being a large and once-popular fish, has embedded ganoid scales that can’t be removed without tearing the skin, so sturgeon is not considered kosher. These are among the most common non-kosher fish people encounter and wonder about.
Sea mammals are forbidden. Whale, dolphin, and manatee are mammals rather than fish. Because they lack fins and scales entirely, they’re forbidden under kashrut, though their mammal status raises additional concerns beyond just the seafood rules.
| Seafood | Kosher? | Reason |
|---|---|---|
| Salmon, tuna, tilapia | ✅ Yes | Fins and removable scales (OU, cRc confirmed kosher) |
| Halibut, cod, flounder | ✅ Yes | Fins and qualifying scales, considered kosher |
| Striped bass, largemouth bass | ✅ Yes | Fins and removable scales, considered kosher (cRc) |
| Herring, sardines, mackerel | ✅ Yes | Qualifying scales, confirmed kosher |
| Shrimp | ❌ No | No fins, no qualifying scales (forbidden by Torah) |
| Lobster, crab | ❌ No | Crustaceans: no fins or qualifying scales (forbidden) |
| Clams, oysters, scallops | ❌ No | Mollusks: no fins or scales, forbidden under kashrut |
| Squid (calamari), octopus | ❌ No | Cephalopods: no fins or scales, not kosher |
| Shark | ❌ No | Placoid scales not halachically valid (OU confirms not kosher) |
| Catfish | ❌ No | No scales at all, forbidden (OU, cRc) |
| Sturgeon | ❌ No | Embedded ganoid scales cannot be removed, not kosher |
| Eel | ❌ No | No qualifying fins or scales, forbidden under Jewish law |
Keeping Kosher with Seafood: Practical Considerations
Keeping kosher when it comes to seafood is straightforward in principle but requires attention at the store and at restaurants. The requirements are binary: fins and removable scales, or it’s not considered kosher. But there are a few specific scenarios where things get more nuanced.
At the fish counter. When buying whole fish or skin-on fillets, you can confirm the species by sight. Whole fresh kosher fish generally doesn’t need a hechsher. The OU and cRc both recognize that while most packaged foods require certification, a whole kosher fish with intact skin and scales is identifiable. Ask the fishmonger for the species name if the label isn’t clear, because fish is frequently sold under multiple market names.
Processed and packaged seafood. Smoked salmon, canned tuna, frozen fillets, and other processed seafood need kosher certification for strictly observant households. Once the scales are removed, you can’t verify the species by sight, and processing facilities may handle non-kosher seafood on shared equipment. For these foods, a hechsher from the OU, Star-K, OK Kosher, or another recognized agency is essential. The cRc explicitly recommends certification for all processed and canned fish to ensure they meet the requirements of kashrut.
At restaurants. Kosher-certified restaurants that are supervised by a mashgiach are the safest option for a seafood meal. At non-kosher restaurants, even if you order a kosher fish species, concerns about shared pans, utensils, and sauces make it complicated. Many observant Jews avoid fish at non-kosher restaurants entirely, while others apply specific leniencies depending on their tradition and rabbinic guidance.
Health and kashrut overlap. Many people who keep kosher find that the kosher-approved fish selection, which is entirely finfish with removable scales, aligns well with health guidelines for seafood consumption. Fish like salmon, sardines, mackerel, and tuna are widely recognized for their health benefits, including omega-3 fatty acids that support cardiovascular health. While the kashrut rules exist for religious reasons, keeping kosher at the seafood counter naturally steers you toward many of the species that health-focused eaters prioritize. That overlap isn’t the purpose of kashrut, but it’s a reality for anyone comparing kosher dietary laws with modern health recommendations on seafood consumption.
When Does Kosher Seafood Need Certification?
The requirements for certification depend on the form the fish comes in. Here’s how to think about it:
Fresh whole fish or skin-on fillets generally don’t need a hechsher. When the skin and scales are intact, you can confirm the species visually, which satisfies the main identification requirement. The OU and cRc both note this standard for whole fresh fish. This applies to a whole salmon at the fish counter, a skin-on striped bass fillet, or a whole tilapia at a fish market.
Processed, smoked, canned, or frozen skinless fillets require certification for strictly observant consumers. Without scales, the species can’t be identified by sight. Processing facilities can handle non-kosher seafood on the same line. Additives and flavorings may include non-kosher ingredients. A hechsher from the OU, Star-K, OK Kosher, or Kof-K ensures the product meets all kashrut requirements throughout processing and packaging.
For anything you’re unsure about, look for a recognized kosher certification or ask your rabbi. The full breakdown of when fish needs certification is in our guide on whether fish needs a hechsher.
Kosher Seafood Is Pareve
All kosher fish is pareve under Jewish law, meaning it’s neither meat nor dairy. You can serve salmon at a dairy meal, pair a kosher fish with a cream sauce, or include it in a pareve dish. Fish doesn’t fall under the meat restrictions that require separate utensils and a waiting period.
One traditional practice is worth knowing about. Many Ashkenazic communities don’t eat fish and meat on the same plate at the same time. It’s not a Torah prohibition but a traditional custom, and keeping the two separate avoids any question. The full halachic explanation is in our guide on Is Fish Pareve?
Check Any Seafood with KosherFish
Not sure whether a specific seafood is considered kosher? The KosherFish lookup tool on the homepage lets you search by name and get the kosher verdict with the reason. Browse the full kosher fish list to see all 291 species, or take the iOS app or Android app with you while shopping. Type in the fish name and get the kosher verdict in seconds.
Frequently Asked Questions About Kosher Seafood
Is seafood kosher?
Some seafood is kosher and some isn’t. Fish with fins and easily removable scales are considered kosher under Jewish dietary law, according to Leviticus 11:9-12. Shellfish like shrimp, lobster, crab, clams, and oysters are not kosher. Neither are squid, octopus, eel, or shark. The Orthodox Union and the Chicago Rabbinical Council both publish fish lists based on this standard of kashrut.
Is shrimp kosher?
No. Shrimp is not kosher. The Torah requires a water creature to have both fins and removable scales (Leviticus 11:9-12). Shrimp has neither, so it’s forbidden under Jewish law. The OU and cRc both list shrimp as not kosher, and no mainstream Orthodox authority permits it. The same ruling applies to prawns and other crustaceans.
Is lobster kosher?
No. Lobster is not kosher. It’s a crustacean with no fins and no qualifying scales, so it’s forbidden under kashrut (Leviticus 11:9-12). No recognized kosher authority permits lobster consumption. The same applies to crab, crayfish, and all other crustaceans. They fail both requirements of Jewish dietary law.
What makes a fish considered kosher?
A fish is considered kosher if it has fins and scales that can be removed without tearing the skin. This comes from Leviticus 11:9-12 and Deuteronomy 14:9-10. According to Jewish law, the qualifying scale types are cycloid and ctenoid. Embedded ganoid scales (sturgeon) and dermal denticles (shark) do not meet the halachic requirements. The Orthodox Union and cRc confirm this standard for all species on their kosher fish lists.
Is calamari (squid) kosher?
No. Calamari and squid are not kosher. Squid is a cephalopod with no fins and no scales of any kind. The Torah’s requirements in Leviticus 11:9-12 disqualify it, and the OU confirms squid is not considered kosher. This applies whether it’s fresh, fried, or in a sauce. Octopus and cuttlefish are in the same category and are both forbidden.
Does canned tuna need to be kosher certified?
Yes, for strictly keeping kosher. Canned tuna is processed with the skin and scales removed, so you can’t verify the species or the processing conditions by sight. The cRc recommends certified canned fish. The OU, Star-K, and OK Kosher all certify canned tuna products to ensure they meet kashrut requirements. Whole fresh tuna or skin-on tuna steaks are different because the identifying features are still visible.
Is eel kosher?
No. Eel is not kosher. Eels lack the fins and removable scales the Torah requires (Leviticus 11:9-12), so they’re forbidden under Jewish dietary law. The OU and cRc both list eel as not kosher. This comes up often in sushi contexts, since unagi (freshwater eel) and anago (saltwater eel) are common sushi and sashimi ingredients. Any roll containing eel is not considered kosher.
Is seafood kosher for Passover?
Kosher fish is permitted during Passover, and the same fins-and-scales rule applies. Salmon, tuna, halibut, and other kosher fish are all allowed. Shellfish and non-kosher fish remain forbidden, as they are throughout the year. One additional consideration: fish during Passover should come certified kosher for Passover if it’s processed or canned, to ensure no chametz was introduced during processing. Gefilte fish is a traditional Passover staple made from kosher finfish and is widely available with Passover certification.
The Bottom Line
Is seafood kosher? Yes and no. Fish with fins and removable scales are considered kosher under Jewish dietary laws: salmon, tuna, tilapia, halibut, cod, mahi-mahi, flounder, bass, herring, sardines, and hundreds more. Shellfish, crustaceans, mollusks, cephalopods, and non-kosher fish like shark, eel, and catfish are forbidden under kashrut. The Torah’s requirements (Leviticus 11:9-12) draw a clear line, and the OU and cRc confirm it for every species on their lists.
Browse the full kosher fish list for all 291 species, or look up any fish at KosherFish.co using the search tool. At the store, the iOS app or Android app gives you the verdict in seconds. For deeper reading, see our guides on what makes a fish kosher, when fish needs a hechsher, and how to buy kosher fish.