helensburgh postcode nswst Home ›› Postcode Finder ›› NSWST ›› Helensburgh Helensburgh local listingsThe suburb of Helensburgh is located in NSW and has a postcode of 2508. Free helensburgh business listing! 1Helensburgh Public School1 Lukin St 02 429413322Holy Cross Primary School1 McMillan St 02 42941588 View more business listings in helensburgh Search and find other Postcodes in New South Wales or widen the search to Postcodes in Australia.