Background: In the era of expanding therapeutic options for mCRPC, there is a growing need to develop an optimal treatment sequence. This real-world study evaluated treatment patterns and outcomes in mCRPC patients. Methods: This retrospective cohort study used the Flatiron prostate cancer core registry (Jan 2013 to Sep 2017) to assess real-world treatment patterns (lines of therapy and transitions to subsequent lines) and outcomes (overall survival, OS) in patients with mCRPC. Descriptive analysis was performed for treatment patterns, and the Kaplan–Meier method was used to analyze OS. Results: This study comprised 2559 patients with mCRPC who received up to three lines of therapy. 23% of patients did not receive a life-prolonging therapy after the initial diagnosis of mCRPC. In the first-line (1L) setting, abiraterone (Abi, 37%) was the most-prescribed therapy, followed by enzalutamide (Enza, 28%) and docetaxel (15%). In the second line (2L), combination therapies were frequent (17%), with rates similar to taxane-based chemotherapy (docetaxel or cabazitaxel). Enza was the most-common 2L therapy used after Abi, and vice versa. Radium-223 (Ra-223) was prescribed as 1L therapy in 5% and 2L therapy in 9% of patients, either as monotherapy or part of a combination regimen. When Ra-223 was used in the 1L setting, similar proportions of patients received subsequent therapy with Enza (14%), Abi (13%), or chemotherapy (11%). Ra-223 was commonly used in the third line (14%), but less frequently than chemotherapy (36%). After each line, ~50% of patients did not receive a subsequent life-prolonging agent. Overall, 66% of patients used bone health agents at any time (denosumab, 48%; zoledronic acid, 24%). The median OS from the diagnosis of mCRPC was 21 months. Conclusions: This real-world study shows that not all patients with mCRPC received a life-prolonging therapy. Among patients who received an anti-cancer therapy, approximately half did not receive a subsequent life-prolonging therapy. Abi and Enza were the most-common 1L therapies, and their back-to-back use was common despite reported cross-resistance and limited benefit.