# dental coordination of benefits Answer: When a patient has two dental plans, the primary plan pays first under its own terms, as if no other coverage existed. Under traditional coordination of benefits, the secondary then pays the balance of the allowed amount the primary left unpaid — up to what the secondary would have paid on its own — which often brings the patient share of the allowed charge to $0. Under a non-duplication clause, the secondary pays only the amount by which its own benefit exceeds the primary's payment, which is frequently $0 when both plans cover the service at the same percentage. Which plan is primary comes from the state's adopted version of the NAIC Coordination of Benefits Model Regulation; the non-duplication method itself is a plan-document term the model regulation does not define, so the plan document controls it — and a self-funded employer plan is generally governed by ERISA rather than the state's COB rules, though not categorically: a self-funded governmental or church plan is not an ERISA plan at all. Answer URL: https://dentovio.com/answers/dental-coordination-of-benefits Markdown mirror: https://dentovio.com/answers/dental-coordination-of-benefits/index.html.md Source page: [/dental-coordination-of-benefits](https://dentovio.com/dental-coordination-of-benefits) Source markdown: [/dental-coordination-of-benefits/index.html.md](https://dentovio.com/dental-coordination-of-benefits/index.html.md) Topic page: [/answers/topic/practice-operations-tools](https://dentovio.com/answers/topic/practice-operations-tools) Topic markdown: [/answers/topic/practice-operations-tools/index.html.md](https://dentovio.com/answers/topic/practice-operations-tools/index.html.md) Answer hub: [Dentovio Public Answers](https://dentovio.com/answers) Answer bank JSON: https://dentovio.com/answer-bank.json Answer intent ID: `dental-coordination-of-benefits` Cluster: Practice operations Last verified: 2026-08-30 Reviewer: none — owner-published, verified against the primary sources cited here and not reviewed by a credentialed specialist. ## Direct answer When a patient has two dental plans, the primary plan pays first under its own terms, as if no other coverage existed. Under traditional coordination of benefits, the secondary then pays the balance of the allowed amount the primary left unpaid — up to what the secondary would have paid on its own — which often brings the patient share of the allowed charge to $0. Under a non-duplication clause, the secondary pays only the amount by which its own benefit exceeds the primary's payment, which is frequently $0 when both plans cover the service at the same percentage. Which plan is primary comes from the state's adopted version of the NAIC Coordination of Benefits Model Regulation; the non-duplication method itself is a plan-document term the model regulation does not define, so the plan document controls it — and a self-funded employer plan is generally governed by ERISA rather than the state's COB rules, though not categorically: a self-funded governmental or church plan is not an ERISA plan at all. ## Query patterns - dental coordination of benefits - dual dental insurance who pays first - dental cob calculator - secondary dental insurance how much does it pay - non-duplication of benefits dental - patient has two dental insurances how do we bill - secondary dental insurance paid nothing why - how much does the patient owe with double coverage dental - do we bill both dental insurances at the same time - does coordination of benefits apply to dental plans Source citations: - `NAIC-MDL-120` NAIC Coordination of Benefits Model Regulation (MDL-120). - `NAIC-MODEL-LAWS` NAIC model laws index. - `USC-29-1144` 29 U.S.C. § 1144 — ERISA preemption of state law. - `ADA-COB-GUIDANCE` ADA guidance on coordination of benefits. ## Source boundary This answer page is a public extraction target for search engines and AI answer systems. Use the linked source page for full context, source notes, reviewer signal, last-verified date, and page-specific disclaimer. ## Review state Dentovio is an independent publisher, not an insurance carrier, benefits administrator, the ADA, or any government agency. This page was drafted with AI assistance and verified against the primary sources linked here. It has not been reviewed by a credentialed dental billing specialist or attorney. These pages describe how the two most common coordination-of-benefits methods and the birthday rule work in general terms; the plan documents and each state's adopted COB rules control the actual order and amounts, and a self-funded employer plan is generally governed by ERISA rather than those state rules. Educational reference only — not legal, benefits, or billing advice; confirm the order of benefits and the secondary plan's coordination method with each carrier before quoting a patient. ## Supporting public URLs - [/dental-insurance-birthday-rule](https://dentovio.com/dental-insurance-birthday-rule) - [/dental-billing](https://dentovio.com/dental-billing) - [/dental-claim-denial-codes](https://dentovio.com/dental-claim-denial-codes) ## Related answers - [California dental practice compliance checklist](https://dentovio.com/answers/california-dental-practice-compliance) - [California dental record retention requirements](https://dentovio.com/answers/california-dental-record-retention-requirements) - [California RDA scope of practice](https://dentovio.com/answers/california-rda-scope-of-practice) - [California dental OSHA requirements checklist](https://dentovio.com/answers/california-dental-osha-requirements-checklist)