e24064 Background: ASCO guidelines recommend early palliative care (PC) for patients with advanced cancer, defined as within eight weeks of diagnosis, to enhance survival and quality of life. It is unclear which subsets of patients are referred “late” to PC and how timing of referral impacts cancer outcomes and end-of-life care. Methods: Patients >18 years with first SO consult between 01/01/2021-06/30/2023 were included. Data on patient demographics, acute healthcare and hospice utilization, cancer treatment and mortality was extracted from the electronic medical record (EMR) and claims database. Early referral to SO was defined as visit < 3 months after diagnosis of advanced disease, delayed referrals > 3 months and late consults as < 30 days from death. We used descriptive statistics to describe patients’ sociodemographics, clinical characteristics and healthcare utilization. Multinomial logistic regression analysis was utilized to evaluate how patient characteristics influenced the timing of referrals. To examine the effects of late referral on inpatient (IP) and intensive care unit (ICU) stay durations, we applied a hurdle model. Results: Total sample included 1229 patients; majority had ECOG < 2 and received one line of treatment at time of consult, 87% had solid tumors, of whom 74% had stage 4 disease. The solid tumors most referred were gastrointestinal cancers (25%), lung cancer (14%) and head and neck cancers (13%). Early referral rates across cancer groups differed significantly 53% Head and Neck, 48% GI, 46% Lung, 43% GYN, 29% GU, 11% Breast, and 31% Other (p < 0.001). The most common reason for referral was physical symptom management (98%). The median ESAS symptom burden was 5 (range 0-10) symptoms. At time of analysis, 431 (35.1%) patients had died of which 256 (59%) were in-hospital deaths. Of the deceased patients, late referral ( < 30 days from death) showed a trend, although not statistically significant, toward higher in-hospital mortality rates, (Odds Ratio: 1.13; 95% CI: 0.57-2.24), and a trend toward reduced likelihood of hospice enrollment(Odds Ratio: 0.73; 95% CI: 0.36-1.49). Notably, late referral significantly increased the duration of IP stays (p < 0.001) and ICU stays (p = 0.004) in last 30 days of life, without change in admission to IP (p = 0.68) or ICU (p = 0.86). Conclusions: The delivery of the guideline-directed "early” consult among patients with advanced cancer is variable. Preliminary analysis showed a trend towards higher in-hospital mortality rates and lower hospice referral for patients referred < 30 days from death among “late” consults. Further subgroup analysis is ongoing. [Table: see text]