GAC

BCBS Prefix GAC

Blue Cross and Blue Shield of Illinois

Illinois • EPO, High-Deductible Health Plan (HDHP), PPO

Billing essentials

Provider phone
(877) 860-2837
Electronic payer ID
00621
Claims mailing address
P.O. Box 650712 Dallas, TX 75265-0712
Timely filing limit
180 daysCompare all plans
Prior authorization phone
(800) 654-7385

Coverage under prefix GAC

EPO

This prefix is associated with an EPO plan. Exclusive Provider Organization coverage combines elements of HMO and PPO plans: members must stay in-network like an HMO, but can self-refer to specialists like a PPO. Out-of-network services are not covered except for emergencies.

HDHP

HDHP (High-Deductible Health Plan) coverage means the member has a higher deductible than traditional plans, often paired with a Health Savings Account (HSA). Most services require the member to pay out-of-pocket until the deductible is met. Preventive care is typically covered before the deductible. Submit claims normally to the payer listed above.

PPO

PPO coverage under this prefix means the member can access any provider. In-network providers have negotiated rates with the plan, while out-of-network providers are reimbursed based on usual and customary charges. Prior authorization is generally not required for routine services but may be needed for high-cost procedures.

About Blue Cross and Blue Shield of Illinois

State's only statewide customer-owned health insurer and independent licensee of the Blue Cross Blue Shield Association. Serves Illinois with commercial, Medicare, Medicaid and other plans.