While suicidal behavior often manifests in adolescence and early adulthood, some people first attempt suicide in late life, often with remarkable lethal intent and determination. Given these individuals' more adaptive functioning earlier in life, they may possess traits that hinder adjustment to aging, such as high conscientiousness, rather than impulsive-aggressive traits associated with suicidal behavior in younger adults. A cross-sectional case-control study was conducted in older adults aged ≥50 (mean: 65), divided into early- and late-onset attempters (age at first attempt ≤ or >50, mean: 31 vs 61), suicide ideators as well as non-suicidal depressed and healthy controls. Personality was assessed in terms of the five-factor model (FFM, n = 200) and five DSM personality disorders analyzed on the trait level as continuous scores (PDs, n = 160). Given our starting hypothesis about late-onset attempters, the FFM dimension conscientiousness was further tested on the subcomponent level. All clinical groups displayed more maladaptive profiles than healthy subjects. Compared to depressed controls, higher neuroticism, and borderline traits characterized both suicide ideators and early-onset attempters, while only early-onset attempters further displayed lower extraversion and higher antisocial traits. Late-onset attempters were similar to depressed controls on most measures, but scored higher than them on orderliness, a conscientiousness subcomponent. While neuroticism, introversion, and cluster B traits are prominent in early-onset suicidal behavior, late-onset cases generally lack these features. In contrast, higher levels of orderliness in late-onset suicidal behavior are compatible with the age-selective maladjustment hypothesis. Key points Personality of elderly attempters differed between those with early- and late-onset first attempts. Early-onset attempters possessed personality traits generally found in younger suicidal populations (high neuroticism, low extraversion, antisocial, and borderline PD traits), supporting that constitutional suicide risk factors persist into late life in some individuals. Late-onset suicide attempters had higher levels of orderliness than non-suicidal depressed participants, suggesting that this generally adaptive trait may facilitate suicidal behavior in a subset of depressed elderly.