26 CFR §25.2502-2

Section 2502(d) provides that the donor shall pay the tax. If the donor dies before the tax is paid the amount of the tax is a debt due the United States from the decedent's estate and his executor or administrator is responsible for its payment out of the estate. (See § 25.6151-1 for the time and place for paying the tax.) If there is no duly qualified executor or administrator, the heirs, legatees, devisees, and distributees are liable for and required to pay the tax to the extent of the value of their inheritances, bequests, devises, or distributive shares of the donor's estate. If a husband and wife effectively signify consent, under section 2513, to have gifts made to a third party during any “calendar period” (as defined in § 25.2502-1(c)(1)) considered as made one-half by each, the liability with respect to the gift tax of each spouse for that calendar period is joint and several (see § 25.2513-4). As to the personal liability of the donee, see paragraph (b) of § 301.6324-1 of this chapter (Regulations on Procedure and Administration). As to the personal liability of the executor or administrator, see section 3467 of the Revised Statutes (31 U.S.C. 192), which reads as follows: