From Consumer Wiki
If a consumer has a problem or question about a hospital bill, no governmental agency will intervene on behalf of the consumer because hospitals are businesses and are free to charge their own fees. However, when consumers have disputes about care, billing practices or charges, they may try to resolve problems by following these steps:
Consult with the management care consultant or patient advocate at the hospital where the service was provided, so the care, billing, financial concerns or other problem may be addressed. The consumer should consult with individuals at the next higher level if resolution does not occur.2.
Consult with the insurance company providing coverage; if there is no resolution; consumer may contact the California Department of Insurance which regulates health maintenance organizations licensed as insurance companies.3.
The Department of Managed Health Care, licenses and regulates health care service plans for HMOs such as Blue Cross, Blue Shield, etc.4.
If there is a problem with a collection agency for an unpaid bill, the consumer can write the collection agency and demand a full accounting and that the collection agency show proof that he/she owes a balance. A collection agency may contact a consumer but cannot threaten physical harm. The collection agency may have to work with the insurance company if the consumer is financially insolvent. The consumer can consult with a private attorney or a county legal aid office in their specific county for assistance.5.
If no resolution occurs, consumer may contact the California Department of Health Services which regulates hospitals for compliance with health codes and other state regulations.