What Is Secondary Insurance
Secondary insurance is your second health plan that pays claims after your primary insurance has processed and paid its portion. It covers some or all of what your primary plan didn't pay, including copays, coinsurance, and deductibles, but only up to its own benefit limits.
How Secondary Insurance Processes Claims
The coordination happens in a specific order. Your primary insurer processes the claim first and sends you an Explanation of Benefits (EOB) showing what they paid and what remains as patient responsibility. Your provider then submits the claim to secondary insurance with a copy of the primary EOB attached. Secondary insurance uses the primary EOB to determine its payment, following its own rules about what it considers medically necessary.
Important: Secondary insurance will not pay more than the primary plan's allowed amount, even if its own fee schedule is higher. If primary allows $1,000 for a procedure but only pays $700 after your deductible, secondary typically covers the remaining $300, not anything beyond the primary's allowed charge.
Secondary Insurance and Denials
Denials from secondary insurance often require different appeal strategies than primary denials. Many secondary insurers will deny claims if the primary insurer determined the service lacked medical necessity. This creates a problem: even if you believe the service was necessary, secondary won't override the primary's decision.
If your primary plan denied a claim, you must appeal to the primary insurer first. Secondary insurance typically won't reconsider until the primary denial is overturned. For internal appeals, check your secondary plan's documentation for the 30 to 180-day appeal window (varies by state). Some states allow external appeals for secondary plans, though fewer than 40% of states have this requirement.
Prior Authorization and Secondary Insurance
Prior authorization requirements apply to both insurers. A claim can be denied by secondary if primary obtained prior authorization but secondary required separate approval. Always verify whether secondary needs its own prior auth before treatment. Providers sometimes miss this step, leaving you responsible for costs secondary would otherwise cover.
Common Questions
- Will secondary insurance pay if I don't meet my primary deductible? Rarely. Most secondary plans require the primary deductible to be met first. Once primary applies your deductible and begins paying, secondary can start covering its portion. Check your secondary plan documents for exceptions.
- Can I use secondary insurance to cover primary's copay or coinsurance? Yes, in most cases. Secondary insurance can pay copays and coinsurance amounts that primary didn't cover, but this counts toward secondary's deductible and out-of-pocket limits.
- What happens if both insurers cover the same service? Coordination of Benefits (COB) rules prevent double payment. Combined payment from both plans cannot exceed 100% of the allowed charge. If primary paid 80% and secondary's rules say it covers 60%, secondary won't pay 60% of the full amount, only enough to reach the 100% ceiling.