Background: Prostate cancer (PCa) is one of the most frequently diagnosed malignancies and a leading cause of cancer-related mortality among men worldwide. Over the past decade, major advances in PCa management, including improvements in early detection, refined risk stratification, novel systemic therapies, advanced radiotherapy techniques, functional imaging, and genomic profiling, have contributed to substantial gains in survival, particularly in high-income countries. However, important survival disparities persist both within and between countries. In low-and-middle-income countries (LMICs), these disparities are often attributed to late-stage diagnosis, socioeconomic disadvantage, and structural barriers to timely and high-quality oncologic care. Notably, even in settings with a universal health care system, formal coverage does not necessarily translate into equitable access to diagnosis, treatment, and follow-up, raising concerns about the real-world performance of health systems in delivering cancer care. Objective: To evaluate disparities in PCa survival according to type of health insurance in Cali-Colombia, a large urban center in an LMIC with a universal health care system. Methods: We conducted a population-based study using data from the Cali Population-based Cancer Registry. The study included men aged ≥50 years, residents of Cali newly diagnosed with PCa between January 2018 and December 2022, with follow-up through December 2025. Tumors were classified according to the International Classification of Diseases for Oncology, Third Edition (ICD-O-3). Net survival (NS) was estimated using the Pohar–Perme method to account for competing causes of death, and age standardization was performed using the International Cancer Survival Standard (ICSS-1). Five-year NS (5-year-NS) estimates were calculated overall and stratified by age at diagnosis, histological grade, tumor characteristics, and health insurance types (public vs. private). Results: A total of 3,444 incident malignant PCa cases were identified during the study period. Nearly half of the patients (49.0%) were aged ≥70 years at diagnosis. Pathology reports were available for 67.8% of cases, among which adenocarcinoma was the predominant histological subtype (93.1%). Low-grade tumors accounted for 20.8% of cases, and 79.1% of patients were affiliated with private health insurance. High-grade tumors were more frequently reported among patients with private insurance compared with those with public insurance (49.4% vs. 34.4%). Overall 5-year-NS was 93.1%. Marked and statistically significant disparities in survival were observed by insurance type: patients covered by public insurance had a 5-year NS of 84.6% (95% CI: 76.5–90.1), compared with 95.8% (95% CI: 93.1–97.4) among those with private insurance, representing an absolute difference of more than 11 percentage points. Despite a higher proportion of high-grade tumors, patients with private insurance consistently demonstrated superior survival outcomes. Conclusions/Implications: Substantial disparities in PCa survival persist within universal health care systems and are strongly associated with type health insurance. These findings suggest that factors beyond formal coverage such as delays in diagnosis, differential access to specialized oncology services, and variations in quality and continuity of care play a critical role in shaping survival outcomes. Strengthening health system capacity, reducing fragmentation across insurance schemes, and ensuring equitable delivery of high-quality cancer care are essential steps toward closing avoidable survival gaps and improving PCa outcomes in LMIC settings.