Venous thromboembolism (VTE) is a significant predictor of worse postoperative morbidity in cancer surgeries. No data have been available for patients with preoperative VTE and upper tract urothelial carcinoma (UTUC) undergoing radical nephroureterectomy (RNU). Our aim was to assess the impact of a preoperative VTE diagnosis on perioperative outcomes in the RNU context.Patients aged 18 yr or older with a UTUC diagnosis undergoing RNU were identified in the Merative Marketscan Research deidentified databases between 2007 and 2021. Multivariable logistic regression adjusted by relevant perioperative confounders was used to investigate the association between a diagnosis of VTE prior to RNU and 90-d complication rates, postoperative VTE, rehospitalization, and total costs. A sensitivity analysis on VTE severity (pulmonary embolism [PE] and/or deep venous thrombosis [DVT]) was examined.Within the investigated cohort of 6922 patients, history of any VTE preceding RNU was reported in 568 (8.21%) cases, including DVT (n = 290, 51.06%), PE (n = 169, 29.75%), and superficial VTE (n = 109, 19.19%). The history of VTE before RNU was predictive of higher rates of complications, the most prevalent being respiratory complications (odds ratio [OR]: 1.78, 95% confidence interval [CI]: 1.43-2.22). Preoperative VTE was found to be associated with an increased risk of VTE following RNU (OR: 14.3, 95% CI: 11.48-17.82), higher rehospitalization rates (OR: 1.26, 95% CI 1.01-1.56) other than home discharge status (OR: 1.44, 95% CI: 1.18-1.77), and higher costs (OR 1.42, 95% CI: 1.20-1.68). Limitations include the retrospective nature and the use of an insurance database that relies on accurate coding and does not include information such as pathologic staging.The presented findings will contribute to the counseling process for patients. These patients may benefit from enhanced pre/postoperative anticoagulation. More research is needed before the following results can be used in the clinical setting.Patients aged 18 yr or older with an upper tract urothelial carcinoma (UTUC) diagnosis undergoing radical nephroureterectomy (RNU) were identified in the Merative Marketscan Research deidentified databases between 2007 and 2021. Multivariable logistic regression adjusted by relevant perioperative confounders was used to investigate the association between a diagnosis of venous thromboembolism (VTE) prior to RNU and 90-d complication rates, postoperative VTE, rehospitalization, and total costs. A sensitivity analysis on VTE severity (pulmonary embolism and/or deep venous thrombosis) was examined. The presented findings will contribute to the counseling of patients with UTUC and preoperative VTE.