One of the leading offender rehab charities, the Langley House Trust, says extra support is particularly needed at HMP Guys Marsh in Dorset, HMP Haverigg in Cumbria and HMP Ranby in Nottinghamshire.
The appeal comes as Ministry of Justice figures released last week show suicides, self-harm and violence reached record high levels in English and Welsh prions in autumn 2016.
Speaking about the difference Christians are already making, the Christian-run Langley House Trust, said: "Churches play an invaluable role in this work.
"From praying, to providing project chaplains and volunteers to giving, they get involved and respond to Jesus' call to support the 'least of these' (Matthew 25).
"We in turn help churches with how to engage with former offenders and provide training and supervision for our volunteers."
The Langley House Trust became a registered charity in 1958 and its first project began in 1959 under the leadership of former prisoner of war, John Dodd.
The organisation is also appealing for help at projects in Bedford, Bradford, Bury, Cheltenham, Coventry, Fleetwood, Lancaster, London, Luton, Northampton, Medway, Rochdale, Somerset, Wakefield and Winchester.
Helping approximately 1,500 men and women each year, the organisation boasts one of the lowest reconviction rates in the country - with just 2.6 per cent of those in there housing going on to be convicted again.
Trevor (not his real name), a former heroin addict and burglar who is now living independently in the community after coming to Langley, said: "I had been in and out of prison so many times and I heard that Langley was a place that would help me stop offending.
"I was not sure what to expect but, well, being here is so much better than I could have imagined."