Background: Real-world survival outcomes in metastatic biliary tract cancer (BTC) are largely unknown. Quoted numbers are often based on reports of clinical trials and hospital registry data and may not be representative of patients treated in the real world. Furthermore, the impact of more widespread adoption of standard combination chemotherapy since 2010 on survival is unclear. We performed a population-based survival analysis of patients who presented with metastatic BTC, including intrahepatic cholangiocarcinoma, extrahepatic cholangiocarcinoma and gallbladder cancer. Methods: Utilizing the Surveillance, Epidemiology, and End Results (SEER) database, we collected data for patients diagnosed with metastatic BTC from 2000 to 2018 and stratified by overall survival (OS) of ≤ 3 months (short-term survivors) or ≥ 12 months (long-term survivors), before and after 2010. Additional patient and tumor characteristics, including anatomic location, prior surgical intervention, age, sex, race, and marital status were retrieved. Survival was analyzed using the Kaplan-Meier method. Multivariate cox regression models assessing effects of patient and tumor characteristics between short-term and long-term survivors were employed. Results: Of the 13,287 cases retrieved, 57% were female. Median age was 68 years (range 10-100). Prognosis correlated with anatomic location, marital status, and period of diagnosis. 41% of patients were short term survivors and only 20% were long term survivors. Median OS was 4.5 months for the entire cohort. Median OS only improved marginally from 3.5 months pre-2010 to 4.5 months post-2010 (p<0.001). Long-term survivors tended to be younger, with a median age at diagnosis of 64 years vs 72 years (p<0.001). Within the long-term survivor cohort, intrahepatic disease was significantly associated with improved outcomes (HR 0.81, 95% CI 0.73 – 0.90, p= 0.001). Conclusions: The real-world prognosis of metastatic BTC is remarkably poorer than described in clinical trials as a large proportion of patients survive less than three months. Over the last decade, the improvement in survival has been minimal.