In most cases, your company must pay payroll taxes to establish a group health insurance plan, and employees must be on your payroll to be eligible to sign up. This means that independent contractors and temporary employees can’t usually be covered under a group plan. In addition, employees who are on unpaid leave may lose coverage while they are absent.
Group health coverage usually must also be offered to a plan member’s spouse and dependent children until the age of 26. Your company may also elect to expand this age limit or extend an offer of coverage to unmarried partners.