As a general rule, expenses incurred in administering a decedent's estate, if not deducted for income tax purposes, and claims against a decedent's estate are deductible for estate tax purposes under Section 2053. That is, such expenses and claims reduce the amount subject to estate tax. (Under Section 2054, losses incurred during the settlement of estates arising from fires, storms, shipwrecks, or other casualties, or from theft, when such losses are not compensated for by insurance or otherwise, are also deductible.)
The IRS recently issued certain final regulations under Section 2053 (reserving certain parts for later regulations) dealing with the estate tax deduction of claims against a decedent's estate and costs of administering the estate, which amend the prior regulations. Proposed regulations were issued in 2007.
Jonathan G. Blattmachr, Mitchell M. Gans, and Diana S.C. Zeydel,
Final Regs. on Deducting Expenses and Claims Under Section 2053-Part 1, 37 Est. Plan 3
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