Concurrent vs. consecutive federal sentences
Multiple terms imposed at the same time run concurrently unless the court orders otherwise; terms imposed at different times run consecutively unless the court orders them concurrent (18 U.S.C. § 3584(a)). BOP then treats multiple terms “as a single, aggregate term” for computation (§ 3584(c)) — one commencement date, one Good Conduct Time calculation on the combined length, one release date. The hard cases are federal-plus-state: whether the federal term runs concurrent with an undischarged state sentence turns on the Judgment's wording and, failing that, on BOP's nunc pro tunc designation decision.
Reviewed against 18 U.S.C. § 3584 and BOP Program Statement 5880.28. Last updated .
How does aggregation change the math?
Worked example
Two consecutive terms: 24 months + 36 months
- Aggregate term: 60 months — computed as one sentence, not two.
- GCT: 5 years × 54 = 270 days on the aggregate (not 108 + 162 computed separately — same result here, but proration and partial-year rounding can differ on odd lengths).
- One statutory release date on the combined term; FSA credits and prerelease windows also run off the aggregate.
Aggregation is why the computation sheet shows a single 'Total Term in Effect' even when the Judgment lists several counts — and why checking that aggregate against the Judgment is step one when a family thinks the math is wrong.
What about a state sentence that's still running?
A federal judge may order the federal term concurrent with an anticipated or existing state term (Setser v. United States, 566 U.S. 231 (2012)), and U.S.S.G. § 5G1.3 tells courts when they should. If the Judgment is silent, the default is consecutive — but the person can ask BOP to designate the state facility for federal service nunc pro tunc (retroactively), which makes the time effectively concurrent. BOP decides those requests under Program Statement 5160.05 after asking the sentencing judge's position.
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The free OutDate calculator applies these rules to a real sentence — Good Conduct Time, First Step Act credits, halfway house and RDAP dates — with every assumption listed next to the answer. No account needed; nothing is stored.
Open the federal release date calculatorFrequently asked questions
Do § 924(c) counts have to run consecutive?
Yes — a § 924(c) firearm term must run consecutive to any other sentence by statute; no Judgment wording can make it concurrent. It still joins the aggregate computation for GCT purposes.
If the judge said 'concurrent with the state case,' why is BOP not counting it?
Federal time normally runs only in federal custody. When the person is serving state time first, BOP implements concurrency by designating the state prison for federal service — check whether that designation was actually made, and request it (with the Judgment language) if not.
Is GCT calculated per sentence or on the total?
On the aggregate. Section 3584(c) directs BOP to treat multiple terms as a single term for administrative purposes, so the 54-days-per-year arithmetic runs once, on the combined length.
Primary sources
Everything on this page is drawn from the statutes, regulations, and BOP program statements below — read them directly:
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Estimates, not promises
This page describes federal law and Bureau of Prisons policy in general terms for education. It is not legal advice, it doesn't account for the facts of any individual case, and no attorney–client relationship is created by reading it. The BOP makes all final release-date determinations. Have an attorney review anything before you file it. Built by OutDate, the federal release date calculator.