Objective The primary objective was to identify specific groups of patients with a first-episode psychosis based on family history, obstetric complications, neurological soft signs, and premorbid functioning. The secondary objective was to relate these groups with cognitive variables. Method A total of 62 first-episode psychoses were recruited from adult and child and adolescent mental health services. The inclusion criteria were patients between 7 and 65years old (real range of the samples was 13–35years old), two or more psychotic symptoms and less than one year from the onset of the symptoms. Premorbid functioning (PAS), soft signs (NES), obstetric complications and a neuropsychological battery (CPT, TMTA/TMTB, TAVEC/TAVECI, Stroop, specific subtest of WAIS-III/WISC-IV) were administered. Results We found three clusters: 1) higher neurodevelopment contribution (N=14), 2) higher genetic contribution (N=30), and 3) lower neurodevelopment contribution (N=18). Statistical differences were found between groups in TMTB, learning curve of the TAVEC, digits of the WAIS and premorbid estimated IQ, the cluster 1 being the most impaired. Conclusions A cluster approach could differentiate several groups of patients with different cognitive performance. Neuropsychological interventions, as cognitive remediation, should be addressed specifically to patients with more impaired results.