28 C.F.R. § 523.20 Good conduct time.
(a) The Bureau of Prisons (Bureau or BOP) awards good conduct time (GCT) credit to inmates under conditions described in this section. GCT credit may be reduced if an inmate:
(1) Commits prohibited acts which result in certain disciplinary sanctions (see part 541 of this chapter); or
(2) Fails to comply with literacy requirements in this section and part 544 of this chapter.
(b) For inmates serving a sentence for offenses committed on or after November 1, 1987:
(1) The Bureau will award inmates up to 54 days of GCT credit for each year of the sentence imposed by the court. Consistent with this methodology, the Bureau will initially determine a projected release date by calculating the maximum GCT credit possible based on the length of an inmate's imposed sentence. The projected release date is subject to change during the inmate's incarceration.
(2) The Bureau will award prorated credit for any partial final year of the sentence imposed, subject to the requirements in this section. Accordingly, BOP calculates the projected GCT credit to be awarded for any portion of a sentence that is less than a full year at a prorated amount.
(3) An inmate may receive up to 54 days of GCT credit on each anniversary date of his or her imposed sentence, subject to the requirements in this section. Credit for the last year of a term of imprisonment is awarded the day after the end of the final “anniversary period,” unless the final year is a complete year, in which case credit for the last year is awarded on the first day of the final anniversary period
(4) When the inmate reaches the Bureau-projected release date, the sentence will be satisfied and the inmate will be eligible for release.
(c) For inmates serving a sentence for offenses committed on or after November 1, 1987, but before September 13, 1994, GCT credit is vested once received and cannot be withdrawn.
(d)(1) For inmates serving a sentence for offenses committed on or after September 13, 1994, but before April 26, 1996, all GCT credit will vest annually only for inmates who have earned, or are making satisfactory progress toward earning, a high school diploma, equivalent degree, or Bureau-authorized alternative program credit (see part 544 of this chapter).
(2) For inmates serving a sentence for an offense committed on or after April 26, 1996, the Bureau will award:
(i) Up to 54 days of GCT credit for each year of the sentence imposed, applied on the anniversary date of his or her imposed sentence, if the inmate has earned or is making satisfactory progress toward earning a high school diploma, equivalent degree, or Bureau-authorized alternative program credit; or
(ii) Up to 42 days of GCT credit for each year of the sentence imposed, applied on the anniversary date of his/her imposed sentence, if the inmate does not meet conditions described in paragraph (d)(2)(i) of this section.
(3) Notwithstanding the requirements of paragraphs (d)(1) and (2) of this section, a noncitizen (inmate who is not a citizen of the United States) who is subject to a final order of removal, deportation, or exclusion, is not required to participate in a literacy program to earn yearly awards of GCT credit. However, such inmates remain eligible to participate in literacy programs under part 544 of this chapter.