Regular soy sauce contains wheat — only gluten-free-labeled tamari or GF soy sauce is safe.
It depends on the type. Regular/traditional soy sauce (Kikkoman regular, La Choy, most Chinese/Japanese and restaurant soy sauce) is brewed from soybeans AND WHEAT — NOT gluten-free. Gluten-free-labeled tamari (San-J Tamari Gluten Free, GFCO-certified), Kikkoman Gluten-Free Soy Sauce (rice-based), and coconut aminos ARE gluten-free. Only soy sauce/tamari explicitly labeled “Gluten Free” is celiac-safe. Restaurants use regular wheat soy sauce by default.
Soy sauce is one of the most important hidden gluten sources in cooking. Traditional soy sauce is brewed from soybeans and wheat — so regular soy sauce is NOT gluten-free. But gluten-free-labeled tamari and GF soy sauce, made without wheat, are safe. The word “Gluten Free” on the label is the dividing line.
Regular Soy Sauce vs. Gluten-Free Tamari
Per Kikkoman’s gluten-free soy sauce information: regular/traditional soy sauce is water, WHEAT, soybeans, and salt — brewed from roughly equal parts soybeans and wheat. Per FDA labeling rules, wheat is a gluten-containing grain — regular soy sauce is NOT gluten-free. Gluten-free options: San-J Tamari Gluten Free (GFCO-certified, no wheat), Kikkoman Gluten-Free Soy Sauce (made with rice instead of wheat), and coconut aminos.
Cross-Contamination Risk
Regular Soy Sauce
High
- Wheat is an intentional brewing ingredient — NOT GF.
- Lite/low-sodium regular soy sauce still contains wheat.
Restaurant
High
- Restaurants overwhelmingly use regular wheat soy sauce by default.
- Hidden in stir-fries, sushi, marinades, dumpling sauce, dressings.
- Ask for / bring GF tamari; confirm the dish uses it.
Home
Low
- Choose a GF-labeled tamari/soy sauce.
- Keep separate from regular soy sauce; don’t share dipping bowls.
Soy Sauce — GF Status
- San-J Tamari Gluten Free — GFCO-certified, no wheat — gluten-free
- Kikkoman Gluten-Free Soy Sauce — made with rice instead of wheat, labeled GF
- Coconut aminos — soy- and wheat-free, naturally gluten-free
- Other “Gluten Free”-labeled tamari/soy sauce — gluten-free
- Regular Kikkoman / La Choy / most Chinese/Japanese soy sauce — contains wheat, NOT GF
- Regular “lite”/”low-sodium” soy sauce — still contains wheat, NOT GF
- Tamari NOT labeled “Gluten Free” — may contain wheat, verify
What to Look For — Or Avoid
- “Gluten Free” labeled tamari (San-J GF, GFCO-certified)
- Kikkoman Gluten-Free Soy Sauce (rice-based) or coconut aminos
- Ingredient list with NO wheat
- Regular/traditional soy sauce (water, wheat, soybeans, salt) — NOT GF
- “Lite”/”low-sodium” regular soy sauce — still wheat
- Restaurant soy sauce / tamari NOT labeled GF — assume wheat
Frequently Asked Questions
Is soy sauce gluten-free?
It depends. Regular/traditional soy sauce (Kikkoman regular, La Choy, most Chinese/Japanese and restaurant soy sauce) is brewed from soybeans AND wheat — NOT gluten-free. Gluten-free-labeled tamari (San-J), Kikkoman Gluten-Free Soy Sauce (rice-based), and coconut aminos ARE gluten-free. Only soy sauce/tamari explicitly labeled “Gluten Free” is celiac-safe.
Why does soy sauce contain wheat?
Traditional soy sauce is brewed by fermenting roughly equal parts soybeans and wheat with salt and water. The wheat is an intentional ingredient that contributes to flavor and fermentation. That’s why regular soy sauce is not gluten-free — wheat is one of the FDA-defined gluten-containing grains.
Is tamari gluten-free?
Only if it’s labeled “Gluten Free.” Tamari is a Japanese soy sauce traditionally made with little or no wheat, but NOT all tamari is gluten-free — some still contains a small amount of wheat. San-J Tamari Gluten Free is GFCO-certified and made without wheat. Always check for the explicit “Gluten Free” label.
Is restaurant soy sauce gluten-free?
Assume not. Restaurants overwhelmingly use regular wheat-containing soy sauce by default — in stir-fries, fried rice, sushi, marinades, dumpling sauce, and dressings. Unless the restaurant specifically confirms a gluten-free tamari, treat any soy-sauce-containing dish as NOT gluten-free. Many celiacs bring their own GF tamari.
Is low-sodium soy sauce gluten-free?
No, not regular low-sodium soy sauce. Reducing the sodium does not remove the wheat — “lite”/”low-sodium” regular soy sauce still contains wheat and is not gluten-free. You need a product specifically labeled “Gluten Free” (low-sodium GF tamari options exist).
What’s the best gluten-free soy sauce substitute?
San-J Tamari Gluten Free (GFCO-certified) is a widely used 1:1 substitute with a near-identical flavor. Kikkoman Gluten-Free Soy Sauce (rice-based) is another option. Coconut aminos is a soy-free, wheat-free alternative (slightly sweeter, lower sodium). All are gluten-free and work in stir-fries, marinades, sushi, and dressings.