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Abstract Sinorhizobium melilotisenses nutrients and compounds exuded from alfalfa host roots and coordinates an excitation, termination, and adaptation pathway during chemotaxis. We investigated the role of the novelS. melilotichemotaxis protein CheT. While CheT and theEscherichia coliphosphatase CheZ share little sequence homology, CheT is predicted to possess an α‐helix with a DXXXQ phosphatase motif. Phosphorylation assays demonstrated that CheT dephosphorylates the phosphate‐sink response regulator, CheY1~P by enhancing its decay two‐fold but does not affect the motor response regulator CheY2~P. Isothermal Titration Calorimetry (ITC) experiments revealed that CheT binds to a phosphomimic of CheY1~P with a K_Dof 2.9 μM, which is 25‐fold stronger than its binding to CheY1. Dissimilar chemotaxis phenotypes of the ΔcheTmutant andcheTDXXXQ phosphatase mutants led to the hypothesis that CheT exerts additional function(s). A screen for potential binding partners of CheT revealed that it forms a complex with the methyltransferase CheR. ITC experiments confirmed CheT/CheR binding with a K_Dof 19 μM, and a SEC‐MALS analysis determined a 1:1 and 2:1 CheT/CheR complex formation. Although they did not affect each other's enzymatic activity, CheT binding to CheY1~P and CheR may serve as a link between signal termination and sensory adaptation.