Is Baking Soda Gluten-Free? And What About Baking Powder?

This question comes up constantly in coeliac forums, and the honest answer is that people are worrying about the wrong tin. Baking soda is one of the few things in your pantry that cannot contain gluten under any circumstances, because it is not made from a plant at all. Baking powder is a different story, and it is the one sitting right next to it on the shelf. If you are going to read a label today, make it that one.

Is baking soda gluten-free?

Yes, in every brand, every time. Baking soda is sodium bicarbonate, a single chemical compound (NaHCO₃) mined from trona ore or produced industrially from soda ash. There is no wheat, barley, rye, or oat anywhere in its production, and there is no plant material in the finished product at all. A box of baking soda is about as related to grain as a box of table salt.

This is why you will notice that many baking soda boxes carry no gluten-free label. Manufacturers do not bother certifying a product that has no plausible route to containing gluten in the first place. The absence of a label here is not a warning sign, which is the opposite of how labels usually work and the reason this question keeps getting asked.

Is baking powder gluten-free?

Usually, but this is the one that genuinely needs checking. Baking powder is not a single compound. It is a blend of three things: an alkali (baking soda), a dry acid that reacts with it when wet, and a starch buffer that keeps the two apart and absorbs moisture so the tin does not fizz itself flat on the shelf.

That starch is the only ingredient in the whole business that could carry gluten. In the United States corn starch is the industry standard, so most American baking powder is gluten-free in practice. The risk rises with imported products and some European brands, where wheat starch is a legitimate and reasonably common choice. Wheat starch is processed to remove most protein, but “most” is not good enough for coeliac disease unless the product is specifically certified.

So the label check is narrow and quick. Find the starch in the ingredients list. If it says corn starch, potato starch, or rice starch, you are fine. If it says wheat starch, put it back unless the packet also carries a certified gluten-free mark.

Which baking powder should you buy if you are coeliac?

Any brand whose starch is corn and which carries a certified gluten-free mark, and most major American brands qualify on the first count. Rather than trusting a brand name that may reformulate or differ by country, build the habit around two lines on the packet: the starch in the ingredients, and a certification mark from a body that tests to 20 parts per million or below. The Coeliac UK and American coeliac organisations both publish current certified lists, and those stay accurate in a way a blog post cannot.

One genuine trap: the same brand can use different formulations in different markets. A baking powder that is corn-starch based in the United States may be wheat-starch based in the United Kingdom or Australia under identical packaging. Check the tin in your hand, not the one you read about online.

Can you make your own gluten-free baking powder?

Yes, and it takes about thirty seconds with two ingredients you probably already have. This is the surest route if you cannot find a certified product or you simply want to stop thinking about it.

1. Measure two parts cream of tartar to one part baking soda. For a single teaspoon of baking powder, that is 1/2 teaspoon cream of tartar and 1/4 teaspoon baking soda.
2. Add one part starch if you are storing it. Corn starch, arrowroot, or rice starch keeps the mix dry and stops it reacting in the jar. Skip this if you are mixing it to use immediately.
3. Whisk thoroughly and use. Homemade baking powder is single-acting, meaning it reacts once when it meets liquid rather than again in the oven heat, so get the batter into the pan promptly.

Cream of tartar, incidentally, is potassium bitartrate, which crystallises inside wine barrels during fermentation. It is a mineral salt with no grain content, so it is inherently gluten-free like the soda it partners.

What is the difference between baking soda and baking powder?

Baking soda needs an acid to work; baking powder already contains one. That single difference explains why recipes call for one, the other, or both. Baking soda is a pure alkali, so it only produces carbon dioxide when it meets something acidic in the batter: buttermilk, yogurt, lemon juice, molasses, brown sugar, or sourdough discard. Baking powder is self-contained, with the acid built in, so it works in a plain batter with nothing sour in it.

The practical upshot for a gluten-free baker is that recipes leaning on baking soda plus an acidic ingredient sidestep the label question entirely. Our gluten-free biscuits and gluten-free cookies both take that route, and both are built on naturally gluten-free flours like sorghum rather than anything needing a certification check.

Does cross-contamination matter for baking soda?

Not meaningfully, and this is where the worry usually outruns the risk. Baking soda is produced in mineral processing facilities, not bakeries or grain mills, so there is no wheat in the building to begin with. The supply chain simply does not intersect with gluten at any point between the ore and the box.

Baking powder is manufactured in food plants that may handle other ingredients, so shared-line contamination is at least conceivable there. In practice it is well down the list of things worth your attention compared with the starch question above, and a certified product settles both concerns at once. The FDA’s gluten-free labelling rule sets that threshold at under 20 parts per million, which is the number certification marks are testing against.

Where cross-contamination genuinely does deserve attention is the whole grains themselves, since oats and naturally gluten-free grains like amaranth are often milled on shared equipment.

Where to go from here

The leaveners are the easy part of a gluten-free pantry. The flour is where the real decisions live, and our gluten-free flour guide ranks eleven of them by what they actually do well. If you would rather not assemble a blend from scratch, a certified gluten-free pancake and waffle mix has the leavening already sorted and correctly labelled. For the grains themselves, the gluten-free grains guide covers which are naturally safe, and is oatmeal gluten free tackles the one grain where the answer is genuinely complicated.