How Much of a 15-Year Federal Sentence Must Be Served?

A 15-year federal sentence is 180 months. Here is how the actual time breaks down under federal law.

The federal system requires inmates to serve at least 85 percent of their sentence. The remaining 15 percent is allocated as good time credit up front, roughly 54 days per year of sentence imposed. That credit is not earned day by day. It is given at the start and can only be lost if your fiance makes serious disciplinary decisions while inside. Assuming he keeps his record clean, he would serve approximately 153 months, or about 12 years and 9 months, before release.

Beyond good time, there is one additional program that can meaningfully reduce the sentence. The Residential Drug Abuse Program, known as RDAP, is a rigorous treatment program for inmates with a documented history of substance abuse. Inmates who qualify, are accepted, and successfully complete RDAP receive up to 12 months off their sentence. On top of that, RDAP completion comes with a guaranteed minimum of six months in a halfway house before final release. That combination of sentence reduction and transitional housing makes RDAP one of the most valuable programs available in the federal system for those who qualify.

Taking good time and RDAP together, a qualified inmate on a 15-year sentence could realistically serve closer to 11 years before transitioning to a halfway house.

Outside of RDAP, the federal system offers a wide range of educational programs, vocational training, and certification courses. Inmates who take full advantage of those programs come out better positioned than when they went in. Encourage your fiance to engage with as many as possible from the beginning. It keeps the mind occupied, builds toward something real, and demonstrates the kind of positive behavior that protects good time credit.

Fifteen years is a long sentence, but the federal system is structured in ways that reward people who use the time constructively. InmateAid was built specifically with federal inmates and their families in mind, and we are here for the whole stretch.