What is the Washington prompt-pay deadline for dental claims, and what interest applies to late payment?

Under WAC 284-170-431 (formerly WAC 284-43-321), the Washington payment deadline is 95% of monthly clean-claim volume paid within 30 days; 95% of monthly volume of all claims paid or denied within 60 days. A carrier failing the standard "shall pay interest on undenied and unpaid clean claims more than sixty-one days old until the carrier meets the standard," assessed at 1 percent per month, calculated monthly as simple interest and prorated for any portion of a month, added to the unpaid claim without the provider submitting an additional claim (WAC 284-170-431(2)(d)). Dental applicability: Dental carriers are reached through the carrier definition rather than the plan definition. A self-funded private-employer (ERISA) plan is generally beyond this statute's reach and runs on the federal claims-procedure clock instead — but that comes from the courts reading 29 U.S.C. § 1144, not from its text, and it is not categorical: a self-funded governmental or church plan is not an ERISA plan at all, § 1144(b)(6) leaves multiple employer welfare arrangements open to state insurance law, and nothing in § 1144 bars a state from reaching the third-party administrator or the network contract.

Dental covered, with caveats · Last verified 2026-08-30

Washington prompt-pay law for dental claims

Washington's prompt-pay law reaches dental claims with caveats. The payment deadline and the interest it carries are below.

WAC 284-170-431 (formerly WAC 284-43-321)

Read the statute text

Payment deadlines

Electronic claims: 95% of monthly clean-claim volume paid within 30 days
Paper claims: 95% of monthly volume of all claims paid or denied within 60 days

Washington's rule is a volume standard written into provider contracts, not a per-claim deadline. Every participating provider contract must set a schedule for prompt payment and include penalties meeting these minimums: 95 percent of the monthly volume of clean claims paid within 30 days of receipt by the carrier or its agent, and 95 percent of the monthly volume of all claims paid or denied within 60 days, except as agreed in writing by the parties on a claim-by-claim basis. A clean claim is one with no defect or impropriety, including no lack of required substantiating documentation or particular circumstance requiring special treatment. Two commonly cited authorities are the wrong ones: RCW 48.43.093 is the emergency-services coverage statute and WAC 284-43-2060 is a prior-authorization rule.

Interest and penalties

A carrier failing the standard "shall pay interest on undenied and unpaid clean claims more than sixty-one days old until the carrier meets the standard," assessed at 1 percent per month, calculated monthly as simple interest and prorated for any portion of a month, added to the unpaid claim without the provider submitting an additional claim (WAC 284-170-431(2)(d)). Because both the payment standard and the interest trigger are tied to the carrier's monthly performance rather than to one claim's due date, a per-claim estimate would misdescribe the rule. Exceptions cover fraud or misrepresentation, denied access to records, force majeure, and strikes.

Does it apply to dental? Dental covered, with caveats

Dental carriers are reached through the carrier definition rather than the plan definition. Chapter 284-170 applies to all health plans and all health carriers subject to Washington jurisdiction, and "health carrier" includes a health care service contractor as defined in RCW 48.44.010 — the form Washington stand-alone dental carriers take. The hedge: WAC 284-170-431 never uses the word "dental," and the chapter's "health plan" definition expressly excludes dental-only and vision-only coverage, so the reach runs through the carrier prong only. The rule also binds only participating (contracted) provider claims and state-regulated carriers.

Self-funded (ERISA) plans: A self-funded private-employer (ERISA) dental plan is generally beyond a state prompt-pay statute's reach: 29 U.S.C. § 1144(b)(2)(B) bars a state from deeming such a plan an insurer, and the courts have read that to keep state insurance regulation off it. The statute itself never uses the words self-funded or prompt pay, and the rule is not categorical — a self-funded governmental or church plan is not an ERISA plan at all, so state law can reach it; § 1144(b)(6) leaves multiple employer welfare arrangements open to state insurance law; and nothing in § 1144 addresses state enforcement against the third-party administrator or the network contract. Where the plan is a self-funded ERISA group health plan, the federal claims-procedure deadlines apply instead: a post-service benefit determination within 30 days (one 15-day extension), at least 180 days to appeal, and an appeal decision within 60 days (or two 30-day levels), under 29 CFR 2560.503-1.

Estimate the late-payment interest

Uses the verified Washington rule (WAC 284-170-431 (formerly WAC 284-43-321)). Estimate only — the statute's own accrual triggers control.

How the claim was submitted

Washington sets a different deadline for each, so this decides which day the field below counts from.

Electronic— 95% of monthly clean-claim volume paid within 30 daysPaper— 95% of monthly volume of all claims paid or denied within 60 days

Claim amount (allowed)Interest statutes run on the payable claim amount, not billed charges.Days past the deadlineDays after the statutory deadline for a electronic claim (95% of monthly clean-claim volume paid within 30 days), not days since submission.

No single formula applies

The Washington standard is volume-based, so a single claim's lateness does not by itself produce an interest figure. Interest of 1% per month, simple and prorated for part of a month, attaches to undenied, unpaid clean claims more than 61 days old, and only while the carrier is failing the 95% standard. The carrier adds it without a second claim from the provider, and it may not be applied to the patient's deductible, copay, or coinsurance.

How we calculate this

The calculator does not show a payable amount for this result; the explanation above states the controlling limitation. The rate and deadline come from WAC 284-170-431 (formerly WAC 284-43-321), read against the statute text linked in the sources on this page (last verified 2026-08-30). Accrual start dates, clean-claim status, safe harbors, and plan funding all affect the real figure — treat this as an estimate for the payer conversation, not a demandable amount.

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Also in the statute

This is a contract-standards floor: the rule requires the payment schedule and penalties to be written into the provider contract and to meet these minimums (WAC 284-170-431(1)).
The 60-day standard is waivable "as agreed to in writing by the parties on a claim-by-claim basis."
The rule was filed in 1999 as WAC 284-43-321 and recodified to WAC 284-170-431 effective April 23, 2016; its substance is unchanged. Chapter 284-170 shows a last update of February 4, 2026.

Payment deadlines

Interest and penalties

Does it apply to dental? Dental covered, with caveats

Estimate the late-payment interest

Also in the statute

Sources (statute text)