When an employee is admitted, the hospital can ask the insurer for a letter of guarantee. If the insurer issues one, it covers the eligible charges up to the plan’s limits, and the hospital bills the insurer directly.
Without a letter of guarantee, the employee may need to pay a deposit on admission and the bill at discharge, then claim from the insurer.
The letter only covers what the plan covers. Charges above the limits, or for a higher ward than the employee’s entitlement, are still the employee’s to pay. For a planned admission, it helps to ask for the letter before the admission date.