Hepatocellular carcinoma (HCC) is a leading cause of cancer and cancer-related deaths in the world. Some of the risk factors for the development of HCC include Hepatitis B virus (HBV), Hepatitis C virus (HCV), chronic alcoholism, autoimmune hepatitis, among others. One manifestation of HCC includes tumor thrombus (TT) to the right atrium (RA), which occurs in 0.67-4.1% of patients with HCC. Our case focuses on a unique presentation of HCC with RA TT with initial symptoms of nausea and vomiting without signs of cardiac decompensation or hemodynamic instability. Although there is no definitive treatment for TT to the RA, there are a variety of proven avenues of management of HCC TT to the RA, especially pertaining to patients with adequate liver function.A 63-year old female with a past medical history of untreated HCV and alcohol abuse with no previously known liver disease or history of liver decompensation, presented with nausea, vomiting, and diarrhea. Initial labs revealed hypovolemic hyponatremia and transaminitis with negative ethanol levels. The model for end-stage liver disease (MELD-Na) score was calculated at 27, and she had a Child-Pugh class C score. Follow up labs were significant for elevated alpha-fetoprotein (AFP). Triple-phase CT of the liver revealed a large liver mass with extension into the RA with TT and necrosis of the liver. An echocardiogram revealed a RA mass versus thrombus. Throughout her hospitalization, she never admitted to cardiac symptoms, including shortness of breath, palpitations, or chest pain. No tachycardia was noted, and her blood pressure remained stable. She was not a candidate for surgery or chemotherapy. The patient declined any heroic measures, and palliative care was consulted for further management. She was transferred to hospice, where she died one week later.There are numerous etiologies and clinical presentations of HCC with TT to the RA. Its disease course is insidious and may not present as symptomatic until there is a sizable tumor burden. Therefore, treatment options for HCC with TT to the RA are reliant on HCC screening for at-risk populations, early diagnosis, and each individual patient's baseline liver function.