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I to have had a large increase.  From owing Fed's $64 to $1K and state from a refund to $1300.  I am completely retired this year drawing SS,IRA,s and a fixed pension plus a p.t. job that stopped during 2018.  I have found that little state tax was taken and will correct that but I can not figure why the increased Fed tax when deductions where the same on all income.  Are IRA'S taxed differently?  That is the change from last years taxes.