Portable medical inhaler systems are prone to bacterial contamination and ingrowth. Here we demonstrate thefirst valved aerosol spray chip, a system that sprays a microjet when actuated and seals against bacterial ingrowth into the spray nozzle in the closed state by a sufficiently small gap. The sealing mechanism is realized by placing a valve seat directly underneath the spray orifices. We fabricated and characterized spray chips with and without valve mechanism and show that they haveindistinguishable spray performance. Our system aims to enable the safe reuse of spray chips for multiple spray operations over an extended period, lowering the cost of treatment while increasing patient compliance.