The circulation of the Charlotte Harbor (CH) estuary is explored with a primitive equation model that encompasses the estuary and the adjacent West Florida Shelf. Tidal forcing is from the shelf through the inlets. We use the M2, S2, K1, and O1 constituents that account for 95% of the shelf tidal variance. River inflows are by the Peace, Myakka, and Caloosahatchee Rivers at their spring 1998 mean values. Wind effects are considered for upwelling or downwelling favorable winds that are either held constant or allowed to oscillate with varying periodicities. These factors are sequentially added to look at their individual and collective influences on the estuary's circulation and salinity fields. Tidal currents are asymmetric and slightly ebb dominant during spring tides. River inflows, combined with tidal mixing, result in a net estuarine circulation by gravitational convection, and the Coriolis acceleration causes the outflowing currents to be stronger and with lower salinity on the western side of the CH portion of the estuary. By virtue of shallow connecting passages the CH portion acts nearly independently from the San Carlos Bay portion of the combined CH estuary system. The addition of wind affects both the instantaneous and net circulation and salinity distributions by increasing mixing and by imposing a force that may add either constructively or destructively to the gravitational convection. The net up-estuary salt flux is also affected by tides and winds through their contributions to the Reynolds' flux, which exceeds the salt flux by gravitational convection alone.