The use of cannabidiol or CBD products has skyrocketed in the last five years due to the alleged therapeutic benefits, a low potential for abuse and lack of the typical psychoactive effects associated with the use of cannabis products containing high levels of ∆9-tetrahydrocannabinol (∆9-THC). In Belgium, CBD-containing e-liquids with a total THC content lower than 0.2% (w/w) are currently legal. In order to verify the compliance of the different CBD-containing e-cigarette liquids that are available to the Belgian population, a method was developed for screening of 17 cannabinoids and to quantify the major cannabinoids such as CBD, CBDA, ∆9-THC and ∆9-THCA. The latter was fully validated using the 'total error' approach, applying accuracy profiles and conforming to ISO17025. None of the analysed samples exceeded the legal limit for the total amount of ∆9-THC present. However, of the 20 CBD-liquids investigated in this study, only 30% of the samples contained an amount of CBD that was within 10% deviation of the label claim. Moreover, the CBD e-liquids labelled "full/broad spectrum" consisted of several minor alkaloids in comparison to the "classic" CBD e-liquids where the acidic forms of the cannabinoids were not present. Currently, no legislation is available for the regulation of CBD e-liquids, however these results indicate that quality controls are pertinent especially concerning the discrepancy in CBD label accuracy.