What OS operating system will be required for 2018 Turbo Tax
Below are the minimum requirements for TurboTax Federal 2018 software installed on a Mac computer. Processor Multi-core Intel Processor with 64-bit required. Monitor 1024x768 screen resolution or higher. Operating Systems macOS Sierra 10.12 or later. RAM 2 GB or more recommended. Hard Disk Space 650 MB for TurboTax. Internet Connection 56 Kbps modem (Broadband connection highly recommended). Required for product updates.
That does not mean that it won't run in earlier systems, just that if might not run properly and won't be supported in earlier systems.