watermans-bay postcode wa Home ›› Postcode Finder ›› WA ›› Watermans-Bay Watermans Bay local listingsThe suburb of Watermans Bay is located in WA and has a postcode of 6020. Free watermans bay business listing! Get the first free listing in watermans bay! Search and find other Postcodes in Western Australia or widen the search to Postcodes in Australia.