Despite the promise of the human chemokine receptor 7 (CCR7) as drug target for the treatment of cancer metastasis and autoimmune diseases, there are no potent and selective CCR7 antagonists known in literature. In this work, a 1,2,5-thiadiazole 1,1-dioxide with low μM activity as a CXCR2 and CCR7 antagonist was selected as starting point for a structure-activity relationship study. The replacement of the central thiadiazole dioxide motif with squaramide led to low nanomolar CCR7 antagonism. Additional systematic structural variations afforded various squaramide analogues that displayed potent CCR7 antagonism in a calcium mobilization assay with IC50 values in the low nM range. Unfortunately, the same compounds also displayed potent CXCR2 antagonistic activity and should therefore be considered as dual CCR7/CXCR2 antagonists.