“Surprise” bills from medical personnel who are not in network, despite working at in-network facilities, are becoming a major scourge for patients. (Photo: Getty)

UnitedHealth Group has warned some 700 hospitals that staffing firm Envision Healthcare could be out of network next year.

Hospitals were warned that they and patients could be in for big bills, according to Modern Healthcare, because of its emergency department billing practices. UnitedHealth blames the failure of contract negotiations between itself and Envision because Envision “demands to be paid much more than Medicare pays for the same services,” says the report.

If the companies do not resolve their differences and extend Envision's in-network status past Dec. 31, patients could be the ones faced with big out-of-network bills if they're treated by an Envision-staffed emergency department or by some other departments for which Envision also provides staff. In addition, the hospitals themselves could find themselves stuck for the bills for uncompensated care.