The aim is to study adults with vascular Ehlers-Danlos syndrome (vEDS) and Loeys-Dietz syndrome (LDS) with regard to sociodemographic characteristics, perceived vascular-and multi-organ symptom burdens, and health services utilization. This is a cross-sectional study. In 2018, a postal questionnaire was sent to 71 individuals with genetically verified LDS types 1-4 or vEDS, age ≥ 18 years, recruited through a National Resource Centre for Rare Disorders in Norway. Eighteen patients with vEDS and 34 patients with LDS subtypes 1-4 participated, the response rate was 74%. Median age was 43.5 (range 18-68) years, and 58% were women. Median age at diagnosis was 34 years (range: 6-63). Severe vascular-and multi-organ symptom burdens were found, and chronic pain was reported by 79%. Most respondents (87%) had cardiovascular surveillance visits, 58% yearly or more often, and still 29% had no antihypertensive medications. Three quarters communicated diagnosis-related concerns with their general practitioner. A considerable group (31%) had left work before retirement age. Healthcare professionals should be aware of the spectrum of health burden in adults with vEDS and LDS. A verification of the diagnosis is crucial to counseling, including medical follow-up, education, and work, and advices on precaution and life style decisions. K E Y W O R D S life experiences, Loeys-Dietz syndrome, vascular and multi-organ symptom burden, vascular Ehlers-Danlos syndrome