Medical Billing in Washington: Payer Landscape, Medicaid & Timely Filing

Washington’s Apple Health (Medicaid) is among the most comprehensive in the US — covering dental, vision, and behavioral health through 5 Managed Care Organizations. The state is a national leader in value-based contracting, and many practices bill under quality metrics tied to reimbursement rates. Timely filing is 12 months for most payers.

5WA Medicaid Plans
365 daysMedicaid Filing Limit
11.6%Natl. Avg Denial Rate
95%+Clean Claim Target
Medical Billing in Washington: The Short Version

Washington's Apple Health delivers Medicaid through five managed care organizations with county-based assignments, while the commercial market is anchored by two independent regional Blues — Premera Blue Cross and Regence BlueShield — that are entirely separate companies. Seattle's tech economy makes self-funded ERISA plans an outsized share of the commercial mix.

Major Payers in Washington

PayerTypeWhat Billing Teams Should Know
Premera Blue CrossCommercial / Blue planLargest WA commercial payer; also serves Alaska
Regence BlueShieldCommercial / Blue planSeparate company from Premera; Cambia family
Kaiser Permanente WashingtonIntegrated HMOFormer Group Health; closed-network dynamics
UnitedHealthcareCommercial / MATech-employer self-funded administration
Aetna / CignaCommercialLarge ASO books for Seattle tech employers
Apple Health (HCA)MedicaidCounty-based MCO assignment

Apple Health: Managed Care Plans

Administered by the Washington State Health Care Authority (HCA). The patient's plan assignment — not just Medicaid eligibility — determines the portal, prior-auth list, and filing rules that apply.

PlanNotes
Molina Healthcare of WashingtonLargest Apple Health plan
Coordinated Care (Centene)Statewide presence incl. foster care contract
Community Health Plan of WashingtonCommunity health center-founded nonprofit
UnitedHealthcare Community PlanStatewide presence
Wellpoint Washington (Elevance)Formerly Amerigroup WA

Timely Filing Limits for Washington Claims

Initial-claim windows for the payers Washington practices bill most. Commercial limits are contract-specific — always confirm against your provider agreement and the payer's current manual.

PayerTimely Filing LimitNotes
Apple Health (WA Medicaid)365 days from date of serviceMCO contract windows may be shorter
Medicare (original)12 months from date of serviceSet by federal law; no contract variation
UnitedHealthcare (commercial)90 days from date of serviceContract-specific; some plans allow 180
Aetna (commercial)120 days from date of serviceContract-specific; verify provider agreement
Cigna (commercial)90 days from date of serviceContract-specific; verify provider agreement
Humana (commercial)90 days from date of serviceAmong the strictest; Medicare Advantage differs

Verified against payer publications at time of writing (July 2026). Filing limits change by contract and plan year — treat this table as a starting point, not a substitute for the payer manual. See our methodology.

Washington Billing Realities to Know

Two Independent Blues

Premera and Regence split the Blue brand in Washington as separate companies — separate credentialing, portals, fee schedules, and filing rules.

Tech ERISA Density

Self-funded tech-employer plans (administered by national carriers) follow plan documents, not state mandates — benefits and appeal rules vary plan by plan.

Kaiser WA Legacy

Kaiser’s acquisition of Group Health left legacy product lines; network status can differ between Kaiser WA products.

Balance Billing Protection Act

Washington’s state surprise-billing law works alongside the federal No Surprises Act for state-regulated plans.

Frequently Asked Questions

Apple Health allows 365 days from date of service for initial claims, administered by the Washington State Health Care Authority (HCA). Managed care plans operating in Washington may apply shorter contractual windows, so always verify each plan's provider manual.
Molina Healthcare of Washington, Coordinated Care (Centene), Community Health Plan of Washington, UnitedHealthcare Community Plan, Wellpoint Washington (Elevance). Each plan maintains its own provider portal, prior authorization list, and claim submission rules — the patient's plan assignment, not just Medicaid status, determines how a claim must be billed.
Premera Blue Cross, Regence BlueShield, Kaiser Permanente Washington, UnitedHealthcare, Aetna / Cigna, alongside Medicare and Apple Health. See the payer landscape table on this page for what billing teams should know about each.
Not to all. Washington's Balance Billing Protection Act covers state-regulated fully-insured plans. Self-funded employer plans — common in Seattle's tech sector — are governed by ERISA and fall under the federal No Surprises Act instead; Washington's state law does not apply to them. When a patient presents an ASO or self-funded card, federal NSA rules govern, not the state act. Always confirm plan funding type before assuming state protections apply.

See How Washington Practices Compare

Benchmark your denial rate, Days in AR, and clean claim rate against 2026 specialty data.

Common Codes Billed in This State

Frequently billed codes in this state’s payer environment, with notes on state-specific rules and common denial patterns.

Code Description State-Specific Note
99213 Office visit, est. patient — level 3 Apple Health MCO determines rate; 5 MCOs operate statewide
99214 Office visit, est. patient — level 4 Value-based contracts may tie reimbursement to quality metrics
99215 Office visit, est. patient — level 5 WA Medicaid covers dental and vision; coordinate billing accordingly
Mod. 93 Telehealth — audio-only Washington allows audio-only telehealth; Apple Health covers
H2019 Therapeutic behavioral services High demand; Apple Health integrates behavioral/physical health
CO-45 Charge exceeds fee schedule Common under value-based contracts with capitated elements

Codes and reimbursement rates change annually. Verify current fee schedules with each payer before billing. Full code lookup →

Medical Billing in Nearby States

Oregon California Nevada