The revised regulation takes effect September 30
On August 31, 2026, the Federal Bureau of Prisons published an interim final rule revising its First Step Act time-credit regulations. The rule is scheduled to take effect on September 30, 2026, and public comments are due the same day. Until the effective date, the published amendment is an upcoming change—not a basis to describe the old regulation as already replaced.
The principal revision removes language that delayed the start of earning First Step Act Time Credits until an eligible person arrived at, or voluntarily surrendered to, the facility designated for serving the sentence. The new text of 28 C.F.R. §523.42(a) states that an eligible inmate begins earning after the term of imprisonment commences. A second revision clarifies a narrow rule for certain United States citizens or nationals transferred from a foreign country to serve a sentence here.
The old designated-facility limitation created a gap after sentencing
The existing regulation generally ties the start of earning to arrival or voluntary surrender at the designated facility. That can leave time between commencement of a federal sentence and arrival at the ultimate BOP institution outside the regulatory earning period, even while an eligible person is in federal custody awaiting designation or transportation.
BOP reports that, using commitment data from 2023 through 2025, the average period from sentencing to arrival at a designated institution was 66.06 days. It estimates that an eligible person could potentially earn an average of 23.81 days of First Step Act Time Credits during that interval. Those figures describe the agency's analysis; they do not promise that every person will receive that amount.
The new starting point follows commencement of the federal sentence
The revised §523.42(a) says: ‘An eligible inmate begins earning FSA Time Credits after the inmate's term of imprisonment commences.’ BOP explains that a federal term generally commences when a person is received in custody awaiting transportation to the official detention facility after the sentence is imposed, or when the person voluntarily surrenders to begin service of the sentence. That explanation tracks 18 U.S.C. §3585(a).
The change can matter to eligible people held in a detention center, transfer center, or other federal placement before arrival at the designated institution. It does not convert pretrial detention into an FSA earning period, and it does not rewrite the separate rules governing prior-custody credit under §3585(b). The sentence-commencement record must be identified accurately.
Time in transit does not generate credits automatically
The revised starting date is only one part of the calculation. Under the First Step Act and BOP's regulations, an eligible person earns credits through successful participation in assigned evidence-based recidivism-reduction programs or productive activities. BOP says eligible people awaiting transport can earn during the newly recognized period by successfully participating in available assigned activities.
That means the custody dates alone do not establish the final credit amount. The individual record should show eligibility, assessment, assigned programming or productive activities, successful participation, excused or unexcused absences, refusals, disciplinary interruptions, and the dates BOP used in its calculation. A potential earning window and an earned-credit balance are different things.
Eligibility exclusions remain unchanged
The interim final rule does not remove the statutory conviction-based exclusions in 18 U.S.C. §3632(d)(4)(D). It also does not make a person eligible merely because the federal sentence has commenced. Citizenship and immigration-related application restrictions, disciplinary consequences, and other governing requirements remain separate issues.
A reliable review begins with the judgment and complete conviction record, including every count and statute. It then compares those statutes to the current exclusions and confirms how BOP coded the person. A description of the offense or a recollection of the plea is not enough when eligibility can turn on the precise statute of conviction.
Ten or fifteen days may be earned for each thirty days of successful participation
The First Step Act generally provides 10 days of time credit for every 30 days of successful participation. An eligible person assessed at a minimum or low risk of recidivism may earn an additional five days for each 30-day period after satisfying the statute's risk-assessment requirements. The 15-day rate therefore should not be assumed for every earning period.
Risk history matters. The file should include PATTERN assessments and reassessments, dates of level changes, needs assessments, program assignments, completion records, and the BOP credit worksheet. If the rate changed, the calculation should divide the history into the appropriate periods rather than apply one rate to the entire sentence.
Earning credits and applying credits remain separate questions
A person may have earned credits without yet satisfying every condition for applying them toward prerelease custody or an earlier start of supervised release. Sections 3624(g) and 3632(d)(4), together with 28 C.F.R. §§523.44 and 523.45, govern when credits may be applied. Risk level, recidivism reduction, placement requirements, sentence timing, detainers, and other legal restrictions can affect the result.
The revised starting-date rule does not erase those requirements. A sound calculation should identify the total credits BOP recognizes, credits disallowed or restored, credits already applied, the projected prerelease-custody date, and whether the person meets the separate conditions for the requested placement or supervised-release result.
First Step Act Time Credits are not statutory good-conduct time
First Step Act Time Credits and good-conduct time are governed by different provisions and do different work. Good-conduct time under 18 U.S.C. §3624(b) reduces the time served in custody toward the sentence's expiration. First Step Act Time Credits under §§3624(g) and 3632(d)(4) can move an eligible person into prerelease custody or, within statutory limits, advance the start of supervised release.
The interim rule addresses First Step Act Time Credits. It does not increase the good-conduct-time rate or merge the two systems. Records and requests should use the correct term so that a dispute about one calculation is not confused with the other.
The treaty-transfer clarification is narrow
The second amendment revises §523.44(a)(3). The general rule continues to restrict application of credits for a person serving a term for a conviction under foreign law. The new language clarifies that the restriction does not bar a transferred United States citizen or national whose foreign sentence has been converted into an equivalent United States Code sentence by the United States Parole Commission under 18 U.S.C. §4106A.
BOP describes this as codifying current practice after appellate litigation. It is not a general rule for every person with a foreign conviction, every immigration case, or every treaty transfer. The transfer documents and Parole Commission determination must be reviewed before treating the exception as applicable.
The rule responds to recent court decisions
BOP states that the starting-date change conforms its regulation to recent federal decisions, including the First Circuit's April 27, 2026 decision in Miles v. Bowers. Those courts concluded that the designated-facility restriction conflicted with the First Step Act's text. The agency chose an interim final rule while still inviting public comment.
That procedural posture matters. The regulation has been published with a future effective date, and the agency may later issue additional guidance or a final response to comments. Calculations should be checked against the rule and BOP policy in force when the agency acts, along with controlling law in the district of confinement.
A useful review starts with dates, assignments, and the BOP worksheet
The practical value of the amendment is record-specific. A review should reconstruct the period from sentence commencement through arrival at the designated institution, identify what BOP assigned and what the person completed, and compare those facts to the agency's earning calculation. It should then separate disputes about eligibility, earning, disallowance, restoration, and application.
If BOP's records appear incomplete or incorrect, the issue should be stated precisely and supported with documents. Administrative-remedy requirements and the proper form of judicial review can depend on the claim, custody location, and controlling law. A general request for ‘all First Step Act credits’ may obscure the exact calculation that needs correction.
- Confirm the sentence-imposition, custody-receipt, voluntary-surrender, designation, transfer, and designated-facility arrival dates.
- Obtain the judgment, statement of reasons, sentence computation, eligibility determination, needs plan, PATTERN history, program assignments, and completion records.
- Compare every statute of conviction to the current exclusion list in §3632(d)(4)(D).
- Separate 10-day and 15-day earning periods and document successful participation for each period.
- Identify disallowed, restored, applied, and unapplied credits, plus the agency's projected transfer and release dates.
- Distinguish an earning dispute from a prerelease-placement, supervised-release, good-conduct-time, or prior-custody-credit dispute.
Limits and caution
The August 31 interim final rule removes a significant timing restriction and may add an earning opportunity for eligible people whose federal sentences have begun but who have not reached their designated institutions. It does not guarantee credits for the entire interval, make an excluded conviction eligible, eliminate successful-participation requirements, or require immediate application of every earned day.
This article provides general educational information, not legal advice, a sentence calculation, a deadline calculation, or a conclusion that any person qualifies for credits or placement. Individual review requires the judgment, statutes of conviction, sentence-commencement record, BOP classifications and worksheets, program history, risk assessments, immigration and detainer information, administrative-remedy history, and current controlling law.