Who Is The Guarantor On Health Insurance? 
Your question does not have an easy or simple answer . When you receive treatment from a medical provider you accept financial responsibility for claims not paid by your health insurance carrier . The health insurance company is a guarantor of sorts -LRB- if you have a fully insured plan -RRB- but there may also be other carriers backing them up . With self funded health insurance your employer or union is the guarantor and they may have reinsurance in place to back them . 