The closest commercial airport is the Seattle Tacoma International Airport, just south of Seattle. Nearly all major airlines fly into SeaTac. There are several car rental agencies that operate out of SeaTac. There is also a shuttle service that will run from SeaTac to several predetermined locations in Kitsap County.
Private plans can also access Kitsap County via the Bremerton National Airport, operated by the Port of Bremerton. Car rental services can be arranged from local agencies also.