In the first article in this series about the IRS’s ability to assess tax and additions thereto, we explored the basics of assessment.  In this second article, we’ll examine deficiencies.  In the third article, we’ll examine termination and jeopardy assessments. Deficiencies, Generally For purposes of income, estate, gift, and excise taxes, a deficiency is the amount by which the tax imposed by the Code exceeds the amount of tax shown on the taxpayer’s return, plus