Estate Planning: Federal Estate Taxes - T. Rowe Price

For 2013, the federal estate tax exemption amount* is $5.25 million per person, with a 40% tax rate on taxable assets over that amount. However, an unlimited amount may be left tax-free to a spouse who is a U.S. citizen. Also, starting in 2013, there is a "portability" provision that potentially can increase the federal estate tax exemption amount to $10.5 million that a surviving spouse can leave estate tax-free to his or her heirs if your will did not provide for a bypass trust.

*Your unified exemption amount is reduced by the amount of any gifts you make during your lifetime that exceed the annual gift tax exclusion amounts, leaving a lesser amount available to offset any potential estate tax liabilities at your death.