Abstract: A fuel water separator filter is described that is configured as a filter-in-filter construction with multiple water separating layers to separate water from the fuel. The fuel water separator filter is configured for use on a suction side of a fuel pump, and includes a neck with a radially outward facing seal that in use seals with the filter housing. The filter housing is formed with an isolated water sump that in use is isolated from water that is stripped from the fuel by the first stage of the outer filter. The isolated water sump is formed by a wall within the housing, instead of relying on an outer diameter seal on the filter to form the water sump.