22 CFR 92.75: Services in connection with income tax returns.

(a) Responsibility. Officers of the Foreign Service are authorized to perform any and all notarial services which may be required in connection with the execution of Federal, state, territorial, municipal, or insular income tax returns. Officers should not give advice on the preparation of tax returns.

(b) Fees. No charge under the caption “Notarial Services and Authentications” should be made for services performed in connection with the execution of tax returns for filing with the Federal or State Governments or political subdivisions thereof. When requested, see item 58(d) of the Tariff of Fees, Foreign Service of the United States of America (§ 22.1 of this chapter).