Inmates were confined to their cells for hundreds of days over just three months for breaking rules at Lancaster Farms Prison, according to Ministry of Justice data.
The Howard League for Penal Reform say punishing inmates with confinement contributes to worsening conditions in prison.
Lancaster Farms inmates committed 641 proven offences between July and September, of which 29resulted in the culprit being confined to a cell.
The offending prisoners received 274 days of confinement – the equivalent of nine months between them.
HM Prison and Probation Service guidance states that adult prisoners can be confined to their cells for up to 21 days for a single offence, with young offenders getting up to 10 days.
Prisoners at Lancaster Farms were most likely to be confined in their cells for non-violent offences, with 25 incidents over the three month period.
Of these, five were for endangering the health , or safety of another person , or being disrespectful or verbally abusive, for which the offenders spent a total of 17 days locked in their cells.
There were five incidents of inmates being disrespectful or verbally abusive, accounting for 35 days in confinement.
Prisoners endangered the health and safety of people around them five times, racking up 59 days in all.
Long periods of cell confinement can cause the mental and physical health of prisoners to deteriorate, according to HM Inspectorate of Prisons.
In a 2017 report, the Inspectorate said it was also concerned that many inmates were spending up to 22 hours in “unpleasant” cells, worsening the impact of extended confinement.
Offenders can be sent to a designated segregation unit, but are often locked up in their own cells.
Howard League chief executive Frances Crook said: “Prisoners punished with confinement will have their things taken away and are locked up with no stimulation.
“If there are cellmates involved, that creates a lot of resentment and tension, since taking away things like TVs and radios effectively punishes them as well.”
The Howard League said it recognises that sanctioning rule breakers is necessary, but said an incentive and praise-focused system would be more effective.
Ms Crook added: “Justice is not a synonym for punishment. Prisons should be trying to create hope for the future, rather than trying to punish their way out of problems.”
An HM Prison Service spokesman said: “It is right that governors who know their prisons best have the freedom to decide how to deal with those who break the rules.
“We are reviewing the existing disciplinary processes as part of our wider programme of prison reform.”
Across England and Wales, nearly 7,000 incidents over the three month period resulted in almost 50,000 days of confinement – the equivalent of 130 years locked up.