Kombucha Alcohol: What You Need to Know About Fermented Drink Alcohol Content

When you buy a bottle of kombucha, a fermented tea drink made with bacteria and yeast. Also known as kombucha tea, it's often marketed as a health tonic—but what you might not realize is that it naturally contains alcohol. Even if you’re drinking it for the probiotics or the tangy flavor, that tiny bit of alcohol is there because fermentation can’t be stopped completely. Yeast eats sugar and turns it into ethanol and carbon dioxide. That’s how beer and wine are made. Kombucha does the same thing—just on a smaller scale.

Most store-bought kombucha has less than 0.5% alcohol by volume (ABV), which is legally considered non-alcoholic in the U.S. But that doesn’t mean it’s zero. Some batches, especially homemade ones, can hit 1% or higher if left to ferment too long. If you’re pregnant, in recovery, or avoiding alcohol for health or religious reasons, even small amounts matter. The fermented drinks, including kombucha, kefir, and some juices aren’t all created equal. A 2021 study from the FDA found that nearly 1 in 10 commercial kombucha products tested had alcohol levels above 0.5%, sometimes up to 3%. That’s more than a light beer.

Manufacturers try to control this by filtering, pasteurizing, or stopping fermentation early. But if you brew your own, you’re in charge of the process—and the alcohol level. Leaving kombucha to ferment for weeks instead of days can turn it into a mildly alcoholic drink. That’s why some people intentionally make "hard kombucha"—it’s a growing trend. But if you didn’t mean to, you might be surprised by what’s in your glass.

What you see on the label isn’t always the full story. Some brands list "trace alcohol" or "naturally occurring alcohol," but don’t give exact numbers. If you’re sensitive to alcohol or need to avoid it entirely, check for third-party lab results or contact the company directly. Not all brands are transparent. And if you’re giving it to kids, watch out—some parents assume it’s safe because it’s "natural" or sold in the health food aisle. But a child’s body processes alcohol differently, and even small amounts can affect them.

There’s no one-size-fits-all answer. Commercial kombucha is usually low-risk, but homemade? That’s a wild card. The same yeast and bacteria that give kombucha its fizz and flavor are the ones making the alcohol. You can’t taste it. You can’t see it. You just have to know what you’re dealing with.

Below, you’ll find real-world breakdowns of what’s in popular brands, how to test your own brew, and why some people get positive results on breathalyzers after drinking kombucha—even when they didn’t mean to. This isn’t about scaring you off. It’s about giving you the facts so you can drink with confidence—or avoid it altogether if you need to.