Pulmonary hypertension (PH), especially pulmonary arterial and chronic thromboembolic pulmonary hypertension (PAH/CTEPH), are rare and progressive conditions. Despite recent advances in treatment and prognosis, PH is still associated with impaired quality of life and survival. Long-term PH-registry data provide information on the changing PH-epidemiology and may help to direct resources to patient's needs. This retrospective analysis of the Swiss Pulmonary Hypertension Registry includes patients newly diagnosed with PH (mainly PAH/CTEPH) registered from January 2001 to June 2019 at 13 Swiss hospitals. Patient characteristics (age, body mass index, gender, diagnosis), hemodynamics at baseline, treatment, days of follow-up, and events (death, transplantation, pulmonary endarterectomy, or loss to follow-up) at last visit were analyzed. Patients were stratified into four time periods according to their date of diagnosis. Survival was analyzed overall and separately for PAH/CTEPH and time periods. 1427 PH patients were included (thereof 560 PAH, 383 CTEPH). Over the years, age at baseline (mean ± SD) significantly increased from 59 ± 14 years in 2001–2005 to 66 ± 14 years in 2016–2019 (p  < 0.001) while the gender distribution tended toward equality. Mean pulmonary artery pressure and pulmonary vascular resistance significantly decreased over time (from 46 ± 15 to 41 ± 11 mmHg, respectively, 9 ± 5 to 7 ± 4 WU, p  < 0.001). Three-year survival substantially increased over consecutive periods from 69% to 91% (for PAH 63%–95%, for CTEPH 86%–93%) and was poorer in PAH than CTEPH independently of time period (p  < 0.001). Most patients were treated with mono- or combination therapy and an increasing number of CTEPH underwent pulmonary endarterectomy (40% 2016–2019 vs. 15% 2001–2005). This long-term PH registry reveals that over two decades of observation, newly diagnosed patients are older, less predominantly female, have less impaired hemodynamics and a better survival.