31 C.F.R. § 10.4
Eligibility to become an enrolled agent, enrolled retirement plan agent, or registered tax return preparer
(a) Enrollment as an enrolled agent upon examination. The Commissioner, or delegate, will grant enrollment as an enrolled agent to an applicant eighteen years of age or older who demonstrates special competence in tax matters by written examination administered by, or administered under the oversight of, the Internal Revenue Service, who possesses a current or otherwise valid preparer tax identification number or other prescribed identifying number, and who has not engaged in any conduct that would justify the suspension or disbarment of any practitioner under the provisions of this part.
(b) Enrollment as a retirement plan agent upon examination. The Commissioner, or delegate, will grant enrollment as an enrolled retirement plan agent to an applicant eighteen years of age or older who demonstrates special competence in qualified retirement plan matters by written examination administered by, or administered under the oversight of, the Internal Revenue Service, who possesses a current or otherwise valid preparer tax identification number or other prescribed identifying number, and who has not engaged in any conduct that would justify the suspension or disbarment of any practitioner under the provisions of this part.
(c) Designation as a registered tax return preparer. The Commissioner, or delegate, may designate an individual eighteen years of age or older as a registered tax return preparer provided an applicant demonstrates competence in Federal tax return preparation matters by written examination administered by, or administered under the oversight of, the Internal Revenue Service, or otherwise meets the requisite standards prescribed by the Internal Revenue Service, possesses a current or otherwise valid preparer tax identification number or other prescribed identifying number, and has not engaged in any conduct that would justify the suspension or disbarment of any practitioner under the provisions of this part.
(d) Enrollment of former Internal Revenue Service employees. The Commissioner, or delegate, may grant enrollment as an enrolled agent or enrolled retirement plan agent to an applicant who, by virtue of past service and technical experience in the Internal Revenue Service, has qualified for such enrollment and who has not engaged in any conduct that would justify the suspension or disbarment of any practitioner under the provisions of this part, under the following circumstances:
(1) The former employee applies for enrollment on an Internal Revenue Service form and supplies the information requested on the form and such other information regarding the experience and training of the applicant as may be relevant.
(2) The appropriate office of the Internal Revenue Service provides a detailed report of the nature and rating of the applicant's work while employed by the Internal Revenue Service and a recommendation whether such employment qualifies the applicant technically or otherwise for the desired authorization.
(3) Enrollment as an enrolled agent based on an applicant's former employment with the Internal Revenue Service may be of unlimited scope or it may be limited to permit the presentation of matters only of the particular specialty or only before the particular unit or division of the Internal Revenue Service for which the applicant's former employment has qualified the applicant. Enrollment as an enrolled retirement plan agent based on an applicant's former employment with the Internal Revenue Service will be limited to permit the presentation of matters only with respect to qualified retirement plan matters.
(4) Application for enrollment as an enrolled agent or enrolled retirement plan agent based on an applicant's former employment with the Internal Revenue Service must be made within three years from the date of separation from such employment.
(5) An applicant for enrollment as an enrolled agent who is requesting such enrollment based on former employment with the Internal Revenue Service must have had a minimum of five years continuous employment with the Internal Revenue Service during which the applicant must have been regularly engaged in applying and interpreting the provisions of the Internal Revenue Code and the regulations relating to income, estate, gift, employment, or excise taxes.
(6) An applicant for enrollment as an enrolled retirement plan agent who is requesting such enrollment based on former employment with the Internal Revenue Service must have had a minimum of five years continuous employment with the Internal Revenue Service during which the applicant must have been regularly engaged in applying and interpreting the provisions of the Internal Revenue Code and the regulations relating to qualified retirement plan matters.
(7) For the purposes of paragraphs (d)(5) and (6) of this section, an aggregate of 10 or more years of employment in positions involving the application and interpretation of the provisions of the Internal Revenue Code, at least three of which occurred within the five years preceding the date of application, is the equivalent of five years continuous employment.
(e) Natural persons. Enrollment or authorization to practice may be granted only to natural persons.
(f) Effective/applicability date. This section is applicable beginning August 2, 2011.