Background Neurocognitive deficits are frequent among male offenders and tend to be associated with a more serious risk of anti‐social activity, but they are not systematically allowed for in rehabilitation programmes. Aim The aim of this study was to evaluate neurocognitive performance in a sample of sentenced Finnish male prisoners and consider the implications for prison programme entry. Methods Seventy‐five sentenced male prisoners were examined using a neurocognitive test battery. Results Depending on the neurocognitive domain, from 5% to 49% of the men demonstrated marked neurocognitive deficits in tests of motor dexterity, visuospatial/construction skills, verbal comprehension, verbal and visual memory and attention shift. Verbal IQ was more impaired than performance IQ. There was no association between most serious offence type and neurocognitive performance, but correlations between attention deficit indices and number of previous convictions suggested that recidivists may have an attention disorder profile. Cluster analysis identified two subgroups of offenders, separated by very poor or merely poor cognitive performance. Motor dexterity, visuo‐construction and verbal memory deficits were not wholly explained by lower IQ measures. Conclusions and implications for practice Our sample was small, but the nature and extent of the neurocognitive deficits found suggest that wider use of neurocognitive assessments, which the men generally tolerated well, could help select those most likely to need offender programmes and that the effectiveness of these may be enhanced by some specific cognitive remediation before progressing to more complex social tasks. Copyright © 2013 John Wiley & Sons, Ltd.