Certain and Immediate Estate Tax Relief Act of 2005 - Restores the tax on estates and generation-skipping transfers and the step-up in basis provisions for property acquired from a decedent, previously repealed by the Economic Growth and Tax Relief Reconciliation Act of 2001 (EGTRRA). Declares that the sunset provision (general terminating date of December 10, 2010) of EGTRRA shall not apply to title V of such Act ( Estate, Gift, and Generation-Skipping Transfer Tax Provisions).
Amends the Internal Revenue Code to: (1) provide for an immediate increase to $3 million of the estate tax exclusion (eliminating the phase-in period); (2) impose a maximum estate tax rate of 47 percent; (3) restore the phaseout of graduated estate tax rates and the unified credit against the estate tax; (4) set forth estate valuation rules for certain transfers of nonbusiness assets; and (5) limit estate tax discounts for certain individuals with minority interests in a business acquired from a decedent.