Washington is one of the few states where payers and providers sat down together and wrote rules for how they would work with each other. The state's administrative simplification program has run that effort since 2009. The result is a set of best practices, laws, and deadlines that make Washington billing more predictable than most states, if you know they exist.
This guide is for therapy, counseling, psychiatric, and speech therapy practices billing commercial plans and Apple Health in Washington. It covers how credentialing changed in 2024, the deadlines payers have to meet, and where practices still lose money.
Two changes that still confuse practices
- Credentialing moved to CAQH. Washington used to run credentialing through a shared state database, ProviderSource. That ended on December 31, 2023. Since January 2024, providers register and attest directly in CAQH and grant each health plan access to their profile.
- The state's payer-provider rules have a new home. Since January 1, 2025, the Foundation for Health Care Quality leads Washington's administrative simplification work. The best practices, the health plan pre-service directory, and the X12 transaction guidance are at qualityhealth.org/adminsimp.
Payer portals haven't changed: many Washington health plans still share one payer login for their provider portals, so the same login covers eligibility, claim status, and prior authorization across plans. The credentialing change above doesn't affect that login.
The Washington best practice recommendations
The 17 best practice recommendations describe how payers and providers in Washington should exchange claims, payments, eligibility, and authorizations. Most were written under the state's 2009 administrative simplification law (ESSB 5346). They are aimed at both sides, but several are directly useful to a small practice:
| Recommendation | What it means for your practice |
|---|---|
| Eligibility and benefits (HIPAA 270/271) | Plans should return behavioral health benefit details electronically. Check eligibility through your clearinghouse or the portal before the first visit, not after the denial. |
| Claim acknowledgement (277CA) | Every batch gets an acknowledgement. A claim that was rejected at the front door was never received, so it doesn't stop the timely filing clock. Check acknowledgements within a day or two. |
| Corrections to professional claims (837P) | Send corrections electronically as replacement claims (frequency code 7) with the original claim number, instead of paper or new claims. |
| Remittance (835) | Payment detail should come back as an ERA with standard codes. If a payer still sends paper, enroll in their ERA and EFT. |
| Claim coding policy and edits | Plans should publish their coding edits, and providers can ask a plan to reconsider an edit. If a plan keeps denying a correctly coded service, there is a formal path to challenge the edit itself, not just the claim. |
| Prior authorization timeframes | Standard notification timeframes and rules for extenuating circumstances. State law now sets shorter deadlines (below). |
Deadlines Washington carriers have to meet
These apply to state-regulated plans: individual, small group, and fully insured group coverage. Self-funded employer plans are governed by federal law and may not follow them, so check the member's card and plan type.
Claim payment
Under WAC 284-170-431, carriers must pay 95% of each month's clean claims within 30 days of receipt, and pay or deny 95% of all claims within 60 days, as the Insurance Commissioner reminded carriers. A clean claim is one with no defect and no missing documentation. A provider contract can set stricter terms. If a payer is routinely past these windows, document it and raise it with your provider representative, and with the Office of the Insurance Commissioner if it continues.
Prior authorization
Since January 1, 2024, state-regulated plans must respond to prior authorization requests within:
| Request | Electronic | Fax, phone, or mail |
|---|---|---|
| Standard | 3 calendar days (not counting holidays) | 5 days |
| Expedited | 1 calendar day | 2 calendar days |
Submitting electronically is the faster path, and the plan's own portal counts. Many outpatient therapy services don't need authorization at all with commercial plans, but psychological testing, intensive outpatient, and some Apple Health services often do. Check each plan's pre-service rules in the health plan pre-service directory.
Credentialing
Washington carriers have 90 days to decide on a credentialing application. Since a 2020 law (ESHB 1552), carriers also can't require any database other than the one the Insurance Commissioner selects (now CAQH), and once a provider is approved they must pay covered services retroactively at the contracted rate:
- New provider with a new contract: back to the contract's effective date.
- Provider joining a group that already has a contract: back to the date the provider submitted a complete application.
That second rule is why the date your application was complete matters. Save the CAQH attestation date, the date access was granted to the plan, and any confirmation that the application was complete. Without them, arguing for retroactive payment is much harder.
Retroactive payment only helps if you hold the claims and bill them once the provider is approved, within the plan's filing limit. Track every session a new clinician sees while credentialing is pending, and don't let those claims age out.
Apple Health (Medicaid)
Washington's Medicaid program, Apple Health, is run by the Health Care Authority. Most members are in managed care plans, and each plan has its own provider contract, credentialing, and claim rules. Providers also need to be enrolled with the Health Care Authority itself.
Timely filing differs by plan. Molina's Washington Apple Health manual, for example, sets 180 days from the date of service for initial claims unless the contract says otherwise, and 24 months from the original remittance for corrections. Don't assume one plan's limit applies to the next.
Behavioral health crisis services are treated as emergency services in Washington since 2022 (E2SHB 1688). That mostly affects crisis teams and facilities, but outpatient practices that coordinate with them should know the billing guidance exists.
A Washington billing checklist
- Give each staff member their own payer portal login, and remove access when someone leaves.
- Keep every clinician's CAQH profile attested and shared with each plan you bill.
- Record the date each credentialing application was complete, for retroactive payment.
- Verify eligibility and behavioral health benefits electronically before the first visit.
- Check 277CA acknowledgements for every batch and fix rejections within two business days.
- Send corrected claims electronically as replacements, with the original claim number.
- Submit prior authorizations electronically to get the 3-day standard timeline.
- Flag any clean claim unpaid after 30 days and follow up with the plan.
When to bring in help
Washington's rules work in your favor, but only if someone is watching acknowledgements, credentialing dates, and payment timelines every week. Sharp Networks Group handles billing and credentialing for therapy and behavioral health practices in Washington and other states, inside the EHR you already use. See how we compare the rules state by state, or schedule a consultation.
Last reviewed October 2026. Laws, plan policies, and filing limits change. Confirm current rules with each plan and with the Office of the Insurance Commissioner.