Due to its unique advantages over radical cystectomy (RC), trimodality therapy (TMT) is increasingly being utilized by patients diagnosed with muscle-invasive bladder cancer (MIBC) who are not suitable for or refuse RC. However, achieving a satisfactory oncological outcome with TMT requires strict patient selection criteria, and the comparative oncological outcomes of TMT versus RC remain controversial.Patients diagnosed with non-metastatic MIBC who underwent TMT or RC were identified from the SEER database during 2004-2015. Before one-to-one propensity score matching (PSM), logistic regression was utilized to identify predictors of TMT. After matching, K-M curves were generated to estimate cancer-specific survival (CSS) and overall survival (OS) with log-rank to test the significance. Finally, we conducted univariate and multivariate Cox analyses to identify independent prognostic factors for CSS and OS.The RC and TMT groups included 5812 and 1260 patients, respectively, and the TMT patients were significantly older than the RC patients. Patients with advanced age, separated, divorced, or widowed (SDW) or unmarried marital status (married as reference), and larger tumor size (< 40 mm as reference) were more likely to be treated with TMT. After PSM, TMT was found to be associated with worse CSS and OS, and it was identified as an independent risk factor for both CSS and OS.MIBC patients may not be carefully evaluated prior to TMT, and some non-ideal candidates underwent TMT. TMT resulted in worse CSS and OS in the contemporary era, but these results may be biased. Strict TMT candidate criteria and TMT treatment modality should be required.© 2023. The Author(s), under exclusive licence to Federación de Sociedades Españolas de Oncología (FESEO).