northampton postcode wa Home ›› Postcode Finder ›› WA ›› Northampton Northampton local listingsThe suburb of Northampton is located in WA and has a postcode of 6535. Free northampton business listing! 1Northampton District High SchoolHarvey Rd 08 993411832St Mary's School26 Mary St 08 99341112 View more business listings in northampton Search and find other Postcodes in Western Australia or widen the search to Postcodes in Australia.