For me, in AU, it's as easy as 30 minutes filling in information in a government web application, namely myGov. Information which is, for the most part, prefill

For me, in AU, it's as easy as 30 minutes filling in information in a government web application, namely myGov. Information which is, for the most part, prefilled for me. myTax is written by the Australian Taxation Office and is fairly simple and effective. It adopts a really simple design where you begin by ticking some boxes about your income sources and deductions, and then you only see the options relevant to you. Tax returns competed via this method are back in less than a month. Probably half the people I know do their own tax returns for free.