BACKGROUND:The Safety Attitudes Questionnaire (SAQ) is one of the most widely used instruments to assess safety culture among healthcare providers. The ambulatory version of the SAQ (SAQ-AV) can be used in the primary care setting. Our study objective was to examine the underlying factors and psychometric properties of the Dutch translation of the SAQ-AV in out-of-hours primary care services. DESIGN:Cross-sectional observational study using a web-survey. SETTING:Sixteen out-of-hours general practitioner cooperatives and two call centers in the Netherlands. PARTICIPANTS:Primary healthcare providers in out-of-hours services. MAIN OUTCOME MEASURES:Item-descriptive statistics, factor loadings, Cronbach's alpha scores, corrected item-total correlations, scale correlations. RESULTS:The questionnaire was answered by 853 (43.2%) healthcare professionals. In the factor analyses, 784 respondents were included; mainly general practitioners (N = 470) and triage nurses (N = 189). Items were included in the analyses based on question type and results from previous studies. Five factors were drawn with reliability scores between .49 and .86 and a good construct validity. The five factors covered 27 of the 62 questionnaire items, with three to five items per factor. CONCLUSIONS:The Dutch translation of the SAQ-AV, with five factors, seems to be a reliable tool for measuring patient safety culture and guide quality improvement interventions in out-of-hours primary care services. The Dutch factor structure differed from the original SAQ-AV and other translated versions. In future studies, the questionnaire should be validated further by examining if there is a relationship between the responses on the SAQ-AV, patient experiences, and the occurrence of adverse events.