B4O

BCBS Prefix B4O

CareFirst BlueCross BlueShield

Maryland/District of Columbia/Northern Virginia • Medicare Advantage, Medicaid, High-Deductible Health Plan (HDHP)

Billing essentials

Provider phone
(800) 842-5975
Electronic payer ID
580
Claims mailing address
10455 Mill Run Circle, P.O. Box 825, Owings Mills, MD 21117
Timely filing limit
180 daysCompare all plans
Prior authorization phone
(866) 773-2884

Coverage under prefix B4O

Medicare Advantage

Under this prefix, the member may have Medicare Advantage coverage administered by this BCBS plan. MA claims are subject to CMS regulations in addition to the plan's own policies. Balance billing restrictions apply. Verify the member's specific MA plan details and confirm the correct payer ID for electronic submission.

Medicaid

Under this prefix, the member may have Medicaid coverage managed by this BCBS plan. Medicaid claims have specific rules around cost-sharing, balance billing, and timely filing that override the plan's standard commercial policies. Contact the plan's Medicaid provider services line for submission details.

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.

About CareFirst BlueCross BlueShield

Independent licensee of the Blue Cross Blue Shield Association serving Maryland, District of Columbia and Northern Virginia.