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I prepared both the 2018 and 2019 returns for him using Turbotax2018 Premier and Turbotax2019 Premier (I have been using Turbotax for years and have both copies onstalled on my PC.  I have created a pdf file for tax filing for each year using the two versions of Turbotax and there is no mention of penalites or fees.  He did file for 2017 tax year and got a refund.  According to each year's version of Turbotax he should be getting a refund for both 2018 and 2019 tax years.  Should he file both returns together in one mailing or should he file each year separately?    He will get the 2019 return in before the April15 due date but the 2018 will be late.  He never filed for an extension on his 2018 taxes.