IRC § 6166 estate-tax deferral (closely-held businesses)
Lets an estate that holds a large closely-held business interest pay federal estate tax in installments over up to 14 years at favorable interest rates, instead of forcing a distressed sale to cover the tax. Relief valve for family-business successions.
IRC § 6166 lets an estate defer and pay federal estate tax in installments over up to 14 years — 5 years of interest-only payments followed by 10 years of principal-plus-interest payments — if a qualifying closely-held business interest makes up more than 35% of the adjusted gross estate. Instead of forcing a fire sale of operating-business equity to pay the estate-tax bill at 9 months, the family can pay over 14 years while the business continues to produce cash flow.
Qualification: (1) the decedent was a U.S. citizen or resident; (2) the interest in the closely-held business exceeds 35% of the adjusted gross estate; (3) the business is an active trade or business (not a passive investment vehicle); (4) for partnership or corporate interests, ownership thresholds in IRC § 6166(b)(1) must be met. Aggregation of multiple qualifying businesses is permitted under § 6166(c).
Interest rate: the special 2% rate under IRC § 6601(j) applies to the tax attributable to the first $1.94M (2026, indexed) of taxable value of the business interest. Tax above that amount accrues interest at 45% of the normal § 6621 underpayment rate. These are meaningful discounts against market financing.
Acceleration risks: the deferred tax is accelerated if (1) the estate disposes of 50% or more of the qualifying interest, (2) the estate fails to make a scheduled installment payment, or (3) certain undistributed-income triggers occur. Disposition planning during the 14-year period is therefore critical.
Tagged 🔴 — § 6166 requires the executor to file a timely election, post security (sometimes via a § 6324A special lien), and manage business operations through the 14-year window. Attorney and CPA coordination required.
State-specific notes
Election is made on Form 706 (federal estate-tax return) at original filing; no automatic extension. Executor should consult experienced estate-tax counsel before filing — missed election cannot be reinstated.
Virginia has no separate state estate tax, so § 6166 deferral only affects the federal tax. Virginia decedents with family businesses are common § 6166 candidates, particularly with Virginia closely-held farming, legal, and professional-practice estates.
West Virginia also has no separate state estate tax — § 6166 applies to federal tax only.
IRC § 6166 is a federal-only election with no Alabama state-tax counterpart because Alabama has no estate tax. Alabama closely-held businesses — particularly family farms and timber operations common in the state — qualify federally under the same rules as any other state. Alabama state-court probate (Ala. Code Title 43) does not affect the § 6166 election, which is made on federal Form 706.
References
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