Federal Prisons in Colorado: A Guide to ADX Florence, USP Florence High, and FCI Englewood

About 90 miles south of Denver in Fremont County sits FCC Florence, a Bureau of Prisons complex with four adjoining facilities at different security levels: the ADX (administrative maximum), USP Florence High (high-security penitentiary), FCI Florence (medium), and the Florence minimum-security camp. Together they hold roughly 1,000+ inmates across security levels.

ADX Florence opened in 1994 and is the only Administrative Maximum U.S. penitentiary in the federal system. It houses inmates the BOP considers the highest security risk in the country — often people who assaulted staff at other facilities, escape risks, or those convicted of terrorism or large-scale violent conspiracies. Notable inmates over the years have included Ted Kaczynski, Zacarias Moussaoui, Dzhokhar Tsarnaev, Terry Nichols, and Robert Hanssen.

Conditions are extreme: most inmates spend roughly 23 hours a day in single-occupant cells with limited human contact. Public interest in the facility is enormous — the term “adx florence” draws an estimated 40,000+ monthly U.S. searches, dwarfing search volume for most other federal prisons.

USP Florence High is a high-security U.S. Penitentiary adjacent to ADX. It houses male inmates classified as high-security based on sentence length, criminal history, history of violence, and prior institutional conduct. Most people are transferred here from lower-security facilities after disciplinary issues or arrive directly after long sentences for violent or organized-crime offenses.

FCI Florence is a medium-security federal correctional institution on the same complex, and an adjacent minimum-security camp houses lower-risk inmates who work in support of the complex. Medium-security placement typically reflects mid-length sentences, some criminal history, and no serious institutional conduct issues.

FCI Englewood, in Littleton just outside Denver, is a low-security federal correctional institution with an adjacent minimum-security satellite camp. It houses male inmates serving low-security sentences — commonly white-collar cases, lower-level drug offenses, and immigration-related convictions with limited criminal history. Englewood is the federal facility most Colorado defendants and families ask about because it sits inside the Denver metro area.

A federal judge imposes the sentence; the Bureau of Prisons decides where you serve it. BOP designation uses a points-based custody classification (Program Statement 5100.08) that draws heavily on facts already in your Presentence Investigation Report — the same document that drives your U.S. Sentencing Guidelines calculation.

The higher your offense level and criminal history category, the longer the guideline range and the more custody-classification points you accumulate. Violence, weapon enhancements, leadership-role adjustments, and long sentences all push security level upward — from minimum (camp) to low (Englewood-type) to medium (FCI Florence) to high (USP Florence High). ADX is reserved for administrative-maximum cases and generally is not an initial designation.

Roughly 390 people a month in the U.S. search “federal prisons in colorado” trying to answer this exact question: where will I (or my loved one) be sent? The honest answer is that the guideline range and PSR content are the biggest levers — which is why the sentencing estimator on this site focuses on getting those inputs right.

Fact: Colorado is home to the only federal supermax facility in the country (ADX Florence). No other state has an ADX-designated federal prison.

Myth: “A Colorado federal case means ADX.” Almost no defendant is designated directly to ADX. The overwhelming majority of federal defendants sentenced in the District of Colorado are designated to low or medium facilities, and many serve time outside Colorado based on bed space and proximity to release residence.

Figure: BOP publishes its designation criteria openly in Program Statement 5100.08 — including the exact point values for offense severity, history of violence, and criminal history — so a defense team can estimate your likely security level before self-surrender.

Myth: “Once designated, you can’t transfer.” Inmates can move down in security level over time through clear conduct and program participation; nearer to release, many move to camps or Residential Reentry Centers.

If you are trying to estimate a likely sentence and security-level outcome, start with the Colorado Sentencing Calculator to get a guideline range, then browse the county guides for how cases move through the District of Colorado.

This page is educational only and is not legal advice. For advice on a specific case, consult a licensed federal criminal defense attorney.