As far as I know, Australia has no tax on gifts. This means, if you gift your wife a sum of money upon your death (in a will or as an intestate), she will not be taxed on this sum on her next tax return. This is subject to exceptions. As with all areas of taxation law (which is subject to change almost every year because of policy changes and is extremely complicated and dense), you should speak with a taxation lawyer to be certain. You can have LawAnswers recommend you a lawyer here: Get Connected with the Right Lawyer for You - LawAnswers.com.au.