The New South Wales Government will apply a four per cent stamp duty surcharge on residential property purchased by overseas buyers from next week. It will also apply a 0.75 per cent annual land tax surcharge on residential real estate owned by foreign persons, starting in the 2017 land tax year.Victoria and Queensland have also moved in this direction. From July Victoria will apply a seven per cent foreign buyer stamp duty surcharge, as well as a 1.5 per cent land tax surcharge.The Queensland Government has introduced a three per cent transfer duty surcharge.At Sydney's median house price of A$995,804, stamp duty for a foreign buyer will increase from just over $40,000 to more than $80,000.Foreign buyers will not be entitled to the standard 12-month deferral of stamp duty payment for off-the-plan purchases and will not get the tax-free threshold on the land tax.A foreign buyer is classified as anyone who is not an Australian citizen or a permanent resident.NSW Treasurer Gladys Berejiklian said the measures would generate around $1 billion of revenue over the next four years.