Federally legal CBD products must contain less than 0.3% concentration of THC. Even at these low levels, depending upon things like your weight, level of physical activity and amount of time you have been taking CBD, it is possible that THC may show up on a drug test. Current tests for THC do not define the concentration of THC, just whether or not it is present in your system. If a drug test is a concern, for employment, or other major factor, then you should choose a THC-FREE CBD product, like an isolate or broad spectrum.