Objectives: Limited data are available on the long-term outcomes in recent years for late HIV diagnosis (LD)., Methods: All subjects with HIV enrolled in the ICONA cohort in 2009-2022 who started antiretroviral treatment (ART) within 4 months from diagnosis were included and divided into: (i) pre-ART CD4 count ≥350/mm 3 without AIDS (non-LD), (ii) pre-ART CD4 count <350/mm 3 without AIDS (LD asymptomatic), and (iii) with AIDS events pre-ART (LD-AIDS). The estimated probability and independent risk for mortality (all-cause and cause-specific) and treatment failure were evaluated., Results: Of 6813 participants (2448 non-LD, 3198 LD asymptomatic, and 1167 LD-AIDS), 161 (2.4%) died after ART initiation. At survival analysis, a higher probability of all-cause mortality has been identified for LD than non-LD (P <0.001) and within the former, for LD-AIDS over LD asymptomatic (P <0.001). After adjusting for confounders, LD showed a higher risk of all-cause mortality (vs non-LD adjusted hazard ratio (aHR) 5.51, P <0.001) and, in particular, being an AIDS presenter predicted a greater risk of all-cause (aHR = 4.42, P <0.001), AIDS-related (adjusted subhazard ratio [aSHR] = 16.86, P <0.001), and non-AIDS-related mortality (aSHR = 1.74, P = 0.022) than the rest of the late presenters. Among the short-term survivors in the LD-AIDS group, the long-term mortality was mediated by the lack of immune recovery at 2 years. Finally, LD compared with non-LD and, particularly, among the former, LD-AIDS over LD asymptomatic showed a greater risk of treatment failure., Conclusions: In recent years, LD subjects, particularly, AIDS presenters, remained at a higher risk of poorer outcomes. Public health strategies for early HIV diagnosis are urgently needed to constrain the mortality gap., Competing Interests: Declarations of competing interest A.M. received speaker honoraria from Gilead Sciences and ViiV Healthcare and travel fees and participated in advisory boards sponsored by ViiV Healthcare. A.C. received funding for scientific advisory boards, travel, or speaker honoraria from Gilead Sciences, ViiV Healthcare, Janssen-Cilag, and MSD. A. Giacomelli reports speaker honoraria for ViiV Healthcare and Gilead Sciences and is an adviser for Janssen-Cilag and Mylan. C.P. received personal fees from Gilead Sciences for a case presentation and a travel grant and has served on an advisory board for Janssen-Cilag; A. Gori received speaker honoraria and fees for attending advisory boards from ViiV Healthcare, Gilead Sciences, Janssen-Cilag, MSD, BMS, Pfizer, and Novartis and received research grants from ViiV, BMS, and Gilead Sciences. A.S. received speaker honoraria or participated in advisory boards sponsored by Gilead Sciences, ViiV Healthcare, MSD, and Janssen-Cilag. A.B. received speaker honoraria and fees for attending advisory boards from Astra-Zeneca, BioMerieux, Janssen-Cilag, Nordic Pharma, Pfizer, Qiagen, SOBI, and ViiV and received research grants from Gilead; G.M. participated in the advisory boards of Gilead Sciences, ViiV Healthcare, Angelini, and Janssen-Cilag and received travel grants from ViiV Healthcare, MSD, and Janssen-Cilag; E.G. received grant support from Gilead Sciences and Mylan and speaker honoraria from Gilead Sciences. C.M. received speaker honoraria or participated in advisory boards sponsored by Gilead Sciences, ViiV Healthcare, MSD, and Janssen-Cilag and received research grants from Gilead Sciences; A.d.M. participated in advisory board of Gilead Sciences, ViiV Healthcare, MSD, Pfizer, and GSK and received research grant from Gilead Science, ViiV Healthcare, Merck Sharp and Dohme, GSK, and Janssen-Cilag; A.A. received research grants from Gilead Sciences, AstraZeneca, and ViiV Healthcare and honoraria from Gilead Science, AstraZeneca, GSK, Pfizer, MSD, Moderna, Mylan, Janssen-Cilag, and ViiV Healthcare; A.C-L., A.T., G.D.G., and G.O. have no competing interest to declare., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)