Excessive degradation of the colonic mucin layer by Bacteroides within the human gut microbiota drives inflammatory bowel disease in mice. Bacterial carbohydrate sulfatases are key enzymes in gut colonization, as they are elevated in human inflammatory bowel disease and correlate with disease severity. Selective inhibitors of carbohydrate sulfatases could function as sulfatase-selective drugs, allowing precise control of sulfatase activity while preserving these otherwise beneficial bacteria. Arylsulfamates are covalent inhibitors that target a catalytic formylglycine residue of steroid sulfatases, which is also conserved in carbohydrate sulfatases. Here, using a library of aryl- and carbohydrate sulfamates, we find that they are ineffective against Bacteroides carbohydrate sulfatases yet can inhibit human gut microbiota species grown on sulfated glycans. Leveraging thermal proteome profiling, we identify a lipid kinase as the target responsible for these effects. This work highlights the imperative for developing specific inhibitors targeting carbohydrate sulfatases and unveils the adverse effect that arylsulfamates have on Bacteroides species of the human gut microbiota.