Estate Tax Portability 2026 Calculator
Portability lets a surviving spouse inherit unused estate tax exemption from the deceased spouse. OBBB 2025 raised the federal exemption to $15 million per individual for 2026, $30 million per married couple. Calculate available exemption.
Federal Estate Exemption 2026
Under OBBB (P.L. 119-21, signed July 4, 2025), the federal estate tax exemption rises to $15 million per individual for 2026 (up from $13.99M in 2025). Married couples can combine via portability for $30M total. Estates above this owe 40% federal estate tax on the excess. The exemption is permanent under OBBB (was previously sunsetting end of 2025).
How Portability Works
Surviving spouse inherits the deceased spouse's unused exemption (DSUE). To claim: executor must file Form 706 (estate tax return) within 9 months of death and elect portability. Even small estates need to file Form 706 to preserve the DSUE — failure to file means losing the deceased's unused exemption forever.
Late Portability Election
Rev. Proc. 2017-34 allows late portability election within 5 years of death without penalty for estates below the filing threshold. This is a critical lifeline for survivors who didn't file Form 706 originally — but only if total combined estates remain below the filing threshold. Larger estates lose this protection.
Source: IRS Form 706 instructions, Rev. Proc. 2017-34, OBBB P.L. 119-21 estate tax provisions. Last updated: May 2026.