Thoracic endovascular aortic repair (TEVAR) is the preferred treatment for complicated type B aortic dissection (TBAD) or intramural hematoma (IMH). This study aimed to investigate the association of the proximal landing zone and its morphology with long-term outcomes in patients with TBAD or IMH. A total of 94 patients who underwent TEVAR for TBAD or IMH between 10/2003 and 01/2020 were included. The cohort was divided according to the proximal landing in Ishimaru zone 2 or 3 and the presence of a healthy landing zone (HLZ; non-dissected or aneurysmatic, ≥2 cm length). Primary outcome was freedom from aortic reintervention. Secondary endpoints were freedom from aortic growth, stroke, spinal cord ischemia, retrograde dissection, proximal stent-graft induced new entry (pSINE), debranching failure, and mortality. Outcomes were assessed using Cox proportional hazard models with mortality as a competing risk. A proximal TEVAR landing in zone 2 was associated with higher rates of reinterventions compared to zone 3 (33% vs. 15%, p = 0.031), spinal cord ischemia (8% vs. 0%, p = 0.037), and pSINE (13% vs. 2%, p = 0.032). No difference was found for the other outcomes, including mortality. Landing in dissected segments was not associated with impaired results. Proximal TEVAR landing in zone 3 may be preferable with regard to long-term aortic reintervention in patients with TBAD or IMH.