If a federal estate tax return does not have to be filed, your basis in the inherited property is its appraised value at the date of death for state inheritance or transmission taxes.
For information on the FMV of inherited property on the date of the decedent’s death, contact the executor of the decedent’s estate.
Please view the IRS link below for more information.
https://www.irs.gov/faqs/interest-dividends-other-types-of-income/gifts-inheritances/gifts-inheritan...