In the United States, people without insurance were more likely to arrive with late-stage disease and had worse short-term survival after cancer diagnosis, according to earlier studies utilising data from the early 2000s. Between 2010 and 2013, 1 of 19 common cancers was diagnosed in adults aged 18 to 64 using the National Cancer Database. With a survival follow-up until December 31, 2019, the authors provide comprehensive information on the associations between the kind of health insurance coverage, the stage at diagnosis, and long-term survival. In comparison to patients with private insurance, Medicaid-insured and uninsured patients had a considerably higher risk of receiving a late-stage (III/IV) cancer diagnosis for all stageable malignancies combined and separately. Patients with Stage I disease who lacked insurance exhibited lower survival rates than patients with Stage II disease who had private insurance for 6 cancer locales and all stageable tumours combined (prostate, colorectal, non-Hodgkin lymphoma, oral cavity, liver, and oesophagus). Patients without private insurance also had lower incidences of leukaemia, brain tumours, and 12 of the 17 stageable malignancies, in addition to having worse overall and stage-specific survival rates for all cancers combined. It was imperative to provide access to comprehensive health insurance coverage in order to improve cancer care and outcomes, particularly the stage at diagnosis and survival.