Brazilian here. For us, there is no third party; we must use the tax filing software from Receita Federal (our IRS), available for free on the website (Java ver

Brazilian here. For us, there is no third party; we must use the tax filing software from Receita Federal (our IRS), available for free on the website (Java version, for desktops), within the website itself (web version), or the smartphone app. This software has been available since the 90s; initially a DOS-only application, later a Windows-only application, then a pair of the Windows-only application and the Java application, then the Windows-only application was dropped in favor of the Java application, and later came the web and smartphone versions. For a while, we could also use the older paper forms, but that hasn't been an option for over a decade.