Background: Medicare’s Oncology Care Model alternative payment program participation requires 24-hr patient access to clinician phone advice. Many participating practices have established oncology urgent care clinics to reduce the frequent ED visits in the early phase after cancer diagnosis. However, little is known about patients’ use of pre-ED visit clinical advice via phone. We combined EHR data on phone/secure messaging encounters, outpatient visits, and regional ED visits, to assess how often patients visit the ED without prior clinical advice, and to compare ED visit severity between those with and without preceding clinical advice. Methods: We linked adults ages 18+ from Parkland Health and Hospital System (PHHS), the Dallas County public safety net system, and UT Southwestern (UTSW) NACR Gold-certified cancer registry (2012-2018), to their respective EHR, and identifiably linked patients to a regional health information exchange of ED and hospital encounters. Exchange data included hospital name, ED disposition, diagnoses, and ED Severity Of Illness. We tallied ED visits within 6 months (180 days) after cancer diagnosis and EHR clinical contacts for 24 hours prior to ED visit (telephone/secure messaging, outpatient visits). After descriptive statistics, we used mixed-effects multivariate logistic regression clustering at patient level to model ED disposition after a pre-ED clinical contact. Results: We matched 8,289 Parkland (54% female, 78% Medicaid/charity assistance) and 10,817 UTSW patients (50% female, 12% Medicaid), who generated 21,009 and 22,696 ED visits, respectively. Two-thirds of all ED visits occurred without preceding clinical contact (70.2% PHHS, 66.7% UTSW); large shares of ED visits were to 67 other regional hospitals (22.2% PHHS, 69.5% UTSW). Telephone encounters and outpatient visits to any specialty were the most common contact before ED visit (UTSW: 28.2 and 12.4%; PHHS: 8.7 and 16.1%), but while nearly all UTSW clinic visits were to oncology, only 30% of PHHS clinic visits were to oncology. Though ED visit severity was slightly higher for ED visits without preceding clinical contact (46% vs. 43% ≥Major severity, p < 0.01), patients were discharged home more often if clinical contact preceded ED visits (aOR of hospitalization 0.82, 95% CI: 0.74 – 0.90). Conclusions: Two-thirds of ED visits occurred without prior clinical contact, and though these no-contact ED visits had higher severity of illness, they were more often discharged home from the ED. Future work should identify patient-oriented options to optimize the use of clinical care and the ED.