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United States · Colorado · Florence

ADX Florence

FederalSupermaxmaleUnder capacity (73%)LowHigh
Verified 20 May 2026 · Data dated 1 Jan 2024
Fresh · 9d ago

Data is aggregated from public sources and may be incomplete or out of date. Always verify with primary sources before acting on any figure. See data sources.

For families

How to send mail, money, and visit ADX Florence

Step-by-step guidance using the United States system — addresses, money services, visit booking, what to bring on your first visit.

Open toolkit

The federal supermax — the highest-security prison in the US federal system. Holds inmates judged 'extreme risks' including terror convicts and prior escapees.

Capacity

490

Current population

360

Occupancy

73%

Year opened

1994

Operational

Facility profile

Operator

Federal Bureau of Prisons

Population held

male

Opened

1994

Region

Colorado

Security level

Supermax

Death-row facility

No

Conditions

Single-cell confinement averaging 22-23 hours per day. Cells include a concrete bed, sink-toilet, and a 4-inch window. Recreation in an individual outdoor cage.

Visiting

Visits by appointment only; non-contact through plexiglass for most inmates. Approved visitor list required, processed by the warden's office.

Mailing

Mail screened by staff. No polaroids, hardcover books, or staples. Address: Inmate Name & Register #, ADX Florence, PO Box 8500, Florence, CO 81226.

Practical info

Inmate phone time is restricted and pre-scheduled. Money for commissary via MoneyGram or Western Union to the BOP Trust Fund.

Known issues

Long-running litigation over solitary confinement of mentally ill prisoners (Cunningham v. BOP, settled 2016).

Notable inmates

Ramzi Yousef, Ted Kaczynski (transferred 2021), Robert Hanssen, Terry Nichols, Zacarias Moussaoui.

Contact & address

5880 State Highway 67 South, Florence 81226

Conditions Risk Score

Derived signal — not a judgement. How it's calculated

5/100
Low concern5/100
Overcrowding
0/30
Oversight reports
0/30
Structural flags
5/15
Death signals
0/15
Conditions text
0/10

What the score is responding to:

  • · Substantial documented known-issues record

Trend over time

Population and occupancy by year. Source: official corrections statistics + oversight reports.

Population held

2018: 410-12.2%2024: 360

Occupancy %

2018: 84.0%-13.1%2024: 73.0%

Compared to other facilities in United States

3134 peers
Conditions risk scorethis: 5/100 · peers avg: 3/100 (+64%)

Higher risk than 79% of peer facilities in United States.

Occupancythis: 73% · peers avg: 74% (0%)
Capacity (beds)this: 490 · peers avg: 1583 (69%)

Reports

  • Cunningham v. BOP — federal settlement15 Nov 2016

    BOP agreed to fundamental reforms in the identification and treatment of mentally ill prisoners at ADX, including the creation of two new mental-health step-down units.

    source

Data completeness

100%

How many of our profile fields are populated. We surface this so families and researchers know the limits.