5 CFR § 842.206 - Involuntary retirement.
(a) An employee, other than an employee entitled to an annuity under § 842.207 or § 842.208, who separates from the service involuntarily after completing 25 years of service, or after becoming age 50 and completing 20 years of service is entitled to an annuity, except as provided in paragraphs (b) and (c) of this section.
(b) An employee who is separated for cause on charges of misconduct or delinquency is not entitled to an annuity under paragraph (a) of this section.
(c) An employee who would otherwise be entitled to an annuity under paragraph (a) of this section is not so entitled if the employee has declined a reasonable offer of another position that meets all of the following conditions:
(1) The offer must be made in writing;
(2) The employee must meet established qualification requirements; and
(3) The offered position must be—
(i) In the employee's agency, including an agency to which the employee would be transferred in a transfer of function(s) between agencies;
(ii) Within the employee's commuting area unless geographic mobility is a condition of the employee's employment;
(iii) Of the same tenure and work schedule; and
(iv) Not lower than the equivalent of two grades or pay levels below the employee's current grade or pay level, without consideration of the employee's eligibility to retain his or her current grade or pay under part 536 of this chapter or other authority. In movements between pay schedules or pay systems, the comparison rate of the grade or pay level that is two grades below that of the current position will be compared with the comparison rate of the grade or pay level of the offered position. For this purpose, “comparison rate” has the meaning given that term in § 536.103 of this chapter, except paragraph (2) of that definition should be used for the purpose of comparing grades or levels of work in making reasonable offer determinations in all situations not covered by paragraph (1) of that definition.
(d) An annuity payable under paragraph (a) of this section commences on the day after separation from the service.