Background: Accurate oncologic staging meeting clinical practice guidelines is essential for guideline adherence, quality assessment, and survival outcomes. However, timely and uniform documentation in the electronic health record (EHR) at the time of diagnosis is a challenge for providers. This quality improvement project aimed to increase provider compliance of timely clinical TNM (cTNM) or pathologic TNM (pTNM) staging for newly diagnosed oncologic patients. Methods: Providers in the following site-specific oncologic teams were included: head and neck, skin, breast, genitourinary, gastrointestinal, lung and thoracic, gynecologic, colorectal, and bone marrow transplant. Interventions to facilitate timely cTNM and pTNM staging included standardized EHR-based workflows, learning modules, stakeholder meetings, and individualized provider training sessions. For most teams, staging was considered compliant if it was completed in the EHR within the first 7 days of the calendar month after the date of the patient visit. Factors associated with staging compliance were analyzed using logistic regression models. Results: From January 1, 2014, to December 31, 2018, 7,787 preintervention and 5,152 postintervention new patient visits occurred. During the preintervention period, staging was compliant in 5.6% of patients compared with 67.4% of patients after intervention (P<.001). In the final month of the postintervention period, the overall staging compliance rate was 78.1%. At most recent tracking, staging compliance was 95%, 97%, and 93% in December 2019, January 2020, and February 2020, respectively. Logistic regression found that increasing years of provider experience was associated with decreased staging compliance. Conclusions: High rates of staging compliance in complex multidisciplinary academic oncologic practice models can be achieved via comprehensive quality improvement and structured initiatives. This approach serves as a model for improving oncologic documentation systems to facilitate clinical decision-making and multidisciplinary coordination of care.