Introduction: Homeless individuals, overrepresented by Veterans, are more likely to have chronic medical conditions and comorbidities. They receive less medical care and have poor health outcomes, though remain understudied. Atrial fibrillation (AF), the most common cardiovascular rhythm disorder, is managed largely through anticoagulation. Direct-acting oral anticoagulants (DOACs) have been shown superior to warfarin anticoagulation in efficacy, safety, and adherence, though costlier. Hypothesis: Homeless Veterans receive a worse standard of care for AF than non-homeless Veterans in terms of initiation of any anticoagulation therapy, and in prescription of DOACs vs warfarin among those who began therapy. Methods: We studied 181,982 Veterans with incident, non-valvular AF in the Veterans Affairs Healthcare system from 2010-2018 who were not previously anticoagulated. Those who died or entered hospice were excluded. We classified Veterans who had experienced homelessness in the 2 years prior to their AF diagnosis using ICD-9/10 diagnosis codes and through VA homeless services use. We used logistic regression to examine the odds of initiation of any, DOAC, or warfarin anticoagulation. Models were adjusted for sociodemographic characteristics (year, age, race, CHA2DS2-VASc stroke risk score, HAS-BLED bleeding risk score, renal disease, BMI) and provider factors (e.g. specialty, had a patient seen a cardiologist within 90 days of their diagnosis). Facility type was modeled as a random effect. Results: Most of our cohort were male (178,400, 98%) and White (155,142, 85.6%). The homeless population of 6,472 was overrepresented by Black patients (1,574, 24.5%) and presented with AF at a younger age. The likelihood of being anticoagulated was lower in all populations before 2014. Having a BMI less than 25, liver disease, or bleeding concerns decreased the likelihood of being anticoagulated, while patients with renal disease were less likely to be prescribed DOACs. Black and Hispanic patients were less likely to be prescribed DOACs, regardless of homelessness status. We found the adjusted odds ratio (aOR) of initiating any anticoagulant therapy for homeless Veterans was 0.71 (95% CI 0.67 - 0.75). Among those who initiated anticoagulation, homeless individuals were less likely than non-homeless Veterans to initiate DOACs (aOR 0.88, 95% CI 0.80-0.96). Conclusions: In a nationwide cohort of Veterans with AF, we found that homeless Veterans were less likely to initiate any anticoagulation, especially more effective DOAC therapy. These findings persisted after adjusting for sociodemographic and clinical factors within an integrated health system with broad access to medical treatment through a uniform drug formulary. Future research must examine and address systematic biases to ensure high quality and equitable care for the most vulnerable populations, including homeless Veterans.