We assessed whether the incidence and outcomes of chronic Graft-versus-Host Disease (cGvHD) after allogeneic hematopoietic stem cell transplantation (alloHSCT) have changed over 30 years. We studied 102,275 adults with hematological malignancies receiving a first alloHSCT from identical siblings or unrelated donors. We compared 3 decades: (I) 1990–1999 vs. (II) 2000–2009 vs. (III) 2010–2019. Over time, patients were older at transplantation, received more PBSC, unrelated donor transplants, reduced intensity conditioning, in vivo T-cell depletion and an ATG prophylaxis, and less TBI. cGvHD incidence at 48 months was 37.3% [36.2–38.4] in I decade vs. 44.9% [44.3–45.5] in II decade vs. 39.1% [38.7–39.5] in III decade, and incidence of extensive cGvHD at 48 months was 18.1% [17.3–19] vs. 22.2% [21.7–22.6] vs. 19.2% [18.9–19.5] over decades. In multivariate analysis, more cGvHD developed in II than in I decade (HR 1.14, 95% CI 1.09–1.21), but no difference was found between III and I decade (HR 1.01, 95% CI 0.96–1.06). Among patients with cGvHD, NRM at 48 months decreased over decades (21.3% [19.8–22.8] vs. 21% [20.3–21.7] vs. 19.7% [19.1–20.2], p < 0.001). Our data show unchanged cGvHD incidences over time and a high NRM in patients after cGvHD diagnosis.