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United Kingdom · Barby · Barby
HM Prison Onley
MaleLow
Verified
Fresh · 2mo ago
Sources last reviewed on
Data is aggregated from public sources and may be incomplete or out of date.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 HM Prison Onley
Step-by-step guidance using the United Kingdom system — addresses, money services, visit booking, what to bring on your first visit.
Background
HM Prison Onley is a Category C men's prison, operated by His Majesty's Prison Service. The prison is named after the lost village of Onley, which is located next to the prison. Onley Prison is in the county of Northamptonshire close to its border with Warwickshire in England. The prison is in the parish of Barby in Northamptonshire. However the postal address of the prison is Willoughby, Warwickshire, therefore most sources list the prison as in Willoughby, Warwickshire.
Source: Wikipedia article lead, CC-BY-SA.
Capacity
100
Current population
—
Occupancy
—
Year opened
1968
Operational
Figures from official sources · verified 28 May 2026 · methodology
Facility profile
Operator
His Majesty's Prison ServicePopulation held
Male
Opened
1968
Region
Barby
Security level
—
Death-row facility
No
Conditions
No conditions summary available yet.
Visiting
No visiting information available.
Mailing
No mailing information available.
Practical info
Contact the operator's website for inmate-specific procedures.
Known issues
No major issues documented in our database.
Contact & address
Onley Park, Barby CV23 8AP
No public contact details available.
Conditions Risk Score
Derived signal — not a judgement. How it's calculated
—
Insufficient data
We don't have enough public data on this facility to score it. Have something to add? Send us a correction.
Related facilities
Same country, matched on type + security level where possible.
- HMP WandsworthLondonHighLocal159% occupancy
- HMP FranklandDurhamMaximumLocal100% occupancy
- HMP BarlinnieGlasgowHighLocal147% occupancy
- HMP Cookham WoodKentHighLocal
- HMP PentonvilleLondonHighYOI137% occupancy
- HMP StyalWilmslowHighClosed female
Compared to other facilities in United Kingdom
583 peersCapacity (beds)this: 100 · peers avg: 579 (83%)
Data completeness
36%How many of our profile fields are populated. We surface this so families and researchers know the limits.
Sources
- OpenStreetMap — OpenStreetMap Contributors
- Wikidata — Wikimedia Foundation
- Wikidata (Q5635242)
- Wikipedia
- See /data-sources for our overall methodology.
Cite this page
Under CC-BY-4.0. Include the URL and access date; the site is a living reference and entries can change.
APA
World Prisons. (2026). HM Prison Onley. Retrieved July 21, 2026, from https://worldprisons.com/prisons/hm-prison-onley
Chicago
"HM Prison Onley." World Prisons. Accessed July 21, 2026. https://worldprisons.com/prisons/hm-prison-onley.
BibTeX
@misc{worldprisons-hm-prison-onley,
author = {{World Prisons}},
title = {HM Prison Onley},
year = {2026},
url = {https://worldprisons.com/prisons/hm-prison-onley},
urldate = {2026-07-21}
}