Q: What is the correct taxpayer identification number (TIN) for a “living trust” (or “revocable trust”)?
A: A common form of a “living trust” (more correctly: “revocable trust”) is where the individual is the grantor, trustee, and primary beneficiary. Under IRC Section 676, the grantor is considered the owner of the property placed into trust because the power to revoke is vested in the grantor, or a nonadverse party or both, and the grantor is both the grantor and the trustee. IRC Section 671 provides that all income from the trust is to be taxed to the grantor. Use the Social Security number of the grantor.
Another common form of a revocable trust is where Husband and Wife are the grantors, co-trustees, and primary beneficiaries. For these type of joint trusts, the correct TIN is the Social Security Number of either Husband or Wife, no differently than you would if it were a joint account between the parties. In the event that your tax advisor has not gotten specific, have that person check IRC Section 671 and 676, and IRS Regulation Section 301-6109(a)(2) and 1.671-4(b).