Is Tamari Gluten Free?

Why tamari isn’t a guaranteed yes

Tamari is a Japanese-style soy sauce, and it has a reputation as the gluten free alternative to regular soy sauce. That reputation is only partly deserved. Traditional soy sauce is made from soybeans and wheat, which is why traditional soy sauce sits on the list of common foods that contain gluten. Tamari is typically made with mostly soybeans and little or no wheat, so it is often a better starting point. But “often” is not “always.” Some tamari products still include wheat as an ingredient, and the word “tamari” on the front of the bottle tells you nothing about what is inside.

Wheat is one of the three main gluten grains, alongside barley and rye. If wheat appears in the ingredient list, that bottle is not for you, however traditional or premium it looks.

Cross-contact and hidden sources

Even a tamari made without wheat as an ingredient can pick up traces of gluten if the facility also makes wheat-based soy sauces or other products on shared equipment. For people with celiac disease, even tiny amounts of gluten can cause damage to the small intestine, so this matters.

Tamari also turns up in places you might not think to check:

• Stir-fry sauces, marinades and glazes
• Salad dressings and dipping sauces
• Flavored nuts, seaweed snacks and rice crackers
• Sushi and takeout dishes, where soy sauce is often served on the side or built into the recipe
• Vegetarian meat substitutes and seasoning blends

Restaurants frequently use regular soy sauce, even when a dish sounds like it should be fine. If you are eating out, ask whether they have a gluten free tamari and whether it is kept separate from regular soy sauce.

How to check the label

Start with the ingredient list. If you see wheat, walk away. Then look for a clear “gluten-free” claim on the package. In the United States, “gluten-free” is a voluntary label claim, and products carrying it must meet the FDA standard of less than 20 parts per million of gluten. That includes fermented and hydrolyzed foods like soy sauce, which have their own compliance requirements under the FDA’s rule. A certified gluten free logo from a third-party organization can add another layer of reassurance.

If a bottle has no gluten-free claim and no wheat in the ingredients, treat it as unconfirmed. Contact the manufacturer and ask about their ingredients and their cross-contact controls. Our guide to gluten-free food labels walks through what each claim does and doesn’t tell you, and this overview on understanding gluten-free labels covers the basics.

What to choose instead

The safest approach is to buy tamari that is clearly labeled gluten-free, ideally with third-party certification, and to check the label again each time you buy, since recipes and suppliers can change. Keep your own bottle at home and, if others in your household use regular soy sauce, use a clean spoon or pour rather than dipping.

If you can’t find a labeled tamari, other seasonings that carry a clear gluten-free label are an option. These include coconut-based liquid seasonings and soy-free alternatives, as long as each product is labeled gluten-free.

Label checking in a busy shop can be tedious. If you want a quicker way to compare products, see how to choose the right gluten checker and our roundup of top gluten-free apps. These tools can be a helpful extra step, but the printed label and the manufacturer remain your best sources of truth.

If you have celiac disease or another gluten-related condition and aren’t sure what is safe for you, ask your doctor or a registered dietitian who knows celiac disease.

This article is for general information only and is not medical advice. If you think you have celiac disease or a gluten-related condition, talk to a doctor or registered dietitian before changing your diet.