Estates of decedents dying on or after January 1, 2011, may elect to transfer any unused estate tax exclusion amounts to the surviving spouse. The amount received by the surviving spouse is called the deceased spousal unused exclusion, or DSUE, amount. If the executor of the decedent's estate elects transfer (through so-called portability) of the DSUE amount, the surviving spouse can apply the DSUE amount received from the estate of his or her last deceased spouse against any estate tax liability arising from subsequent lifetime gifts and transfers at death.
The last deceased spouse is the most recently deceased person who was married to the surviving spouse at the time of that person's death. The identity of the last deceased spouse is determined as of the day a taxable gift is made and is not impacted by whether the decedent's estate elected portability or whether the last deceased spouse had any DSUE amount available. Remarriage also does not affect the designation of the last deceased spouse and does not prevent the surviving spouse from applying the DSUE amount to taxable transfers.
When a taxable gift is made, the DSUE amount received from the last deceased spouse is applied before the surviving spouse's basic exclusion amount. A surviving spouse who has more than one predeceased spouse is not precluded from using the DSUE amount of each spouse in succession. A surviving spouse may not use the sum of DSUE amounts from multiple predeceased spouses at one time nor may the DSUE amount of a predeceased spouse be applied after the death of a subsequent spouse.
A nonresident surviving spouse who is not a citizen of the United States may not take into account the DSUE amount of a deceased spouse unless allowed by treaty.