Background: Outreach psychiatric emergency services play an important role in all stages of a suicidal crisis; however, empirical assessment data are scarce. This study describes characteristics of patients assessed by these services and involved in suicidal crises. Method: During a 5-year period, detailed information from psychiatric emergency service assessments was recorded; 14,705 assessments were included. Characteristics of patients with/without suicidal behavior and with/without suicide attempts were compared. Outcomes were adjusted for clustering of features within individual patients. Results: Suicidal behavior was assessed in 32.2% of patients, of whom 9.2% attempted suicide. Suicidal behavior was most commonly associated with depression or adjustment disorder and these patients were referred to the service by a general practitioner or a general hospital, whereas those who attempted suicide were less likely to be referred by a general practitioner. Those who attempted suicide were more likely to be female and have had a referral by a general hospital. Self-poisoning by medication was the most common method of attempting suicide. Limitations: Bias could be due to missed or incomplete assessments. Primary diagnoses were based on clinical observation at the time of the assessment or on the primary diagnosis previously recorded. In addition, suicidal behavior or attempted suicide might have been underestimated. Conclusions: Suicidal behavior is commonplace in assessments by psychiatric emergency services. Suicidal patients with/without a suicide attempt differed with respect to demographic features, primary diagnoses, and referring entities, but not with respect to treatment policy. About 40% of the suicidal patients with/without an attempt were admitted following assessment.