The Estate Tax is Permanent… Right?

The concerns regarding any decrease in the federal estate and gift tax exemptions were alleviated with the passage of the Taxpayer Relief Act of 2012 (ATRA) which was signed into law on January 2nd of this year. Although the tax rates for those whose estates are higher for those with estates greater than five million dollars, the estate tax is now permanent, right? If so, why are estate planning attorneys still urging their wealthy clients, including those with estates of less than five million dollars, to estate plan without further procrastination. What are their concerns and is it important enough to heed their advice?