How does secondary insurance get billed?

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You can bill secondary insurance by following the step-by-step guidance provided in resources like the Billing Secondary Claims Guide.

Step-by-Step Billing Process

  • Verify both policies: Check eligibility and confirm Coordination of Benefits (COB) for both primary and secondary insurance before treatment.
  • Bill the primary payer first: Submit the initial claim to the primary insurance company and wait for it to process.
  • Review the primary EOB: Obtain the primary insurer's Explanation of Benefits (EOB) or Electronic Remittance Advice (ERA) to see what was paid, adjusted, or left as patient responsibility.
  • Submit the secondary claim: Create the secondary claim using the same CPT or service codes, and attach or enter the primary insurance's payment and adjustment data along with a copy of the primary EOB.

Why is my secondary insurance not paying?

Your secondary insurance may not be paying because of an uncompleted Coordination of Benefits (COB) process, missing primary paperwork, or because the primary insurance payment already met or exceeded the secondary plan's allowable amount.

Common Reasons Your Secondary Insurance Won't Pay

  • Missing Primary EOB: The secondary insurance requires a copy of the primary insurer's Explanation of Benefits (EOB) showing what was paid or applied to your deductible before they will process the claim.
  • Coordination of Benefits (COB) Not Updated: The secondary insurance company does not have on file that your primary insurance already processed and paid the claim, or they have the primary and secondary order reversed.
  • Primary Allowable Exceeds Secondary Rates: If your primary insurance's allowed amount for a service is higher than or equal to what the secondary insurance would have allowed total, the secondary plan pays $0.
  • Primary Deductible Not Met: If the primary insurance applied the cost to your deductible rather than paying it, some secondary plans will not cover that remaining balance until the primary deductible is fully satisfied.
  • Non-Covered Services: If your primary insurance denied a service because it lacked medical necessity or wasn't a covered benefit, your secondary insurance will typically deny it as well.
  • Timely Filing Deadlines Passed: The doctor's office or you waited too long to submit the claim to the secondary insurance after the primary EOB was issued.

Does primary insurance send EOB to secondary insurance?

No, the primary insurance company generally does not automatically send its Explanation of Benefits (EOB) or claim payment data to the secondary insurance company.

How Secondary Billing Works

  • Provider or Patient Responsibility: The healthcare provider or the patient must submit the claim to the secondary insurance.
  • Attaching the Primary EOB: You or your billing department must include a copy of the primary insurance's EOB along with the secondary claim form.
  • Crossover Claims Exception: In some specific automated networks—such as Medicare crossing over to a Medigap secondary plan—the primary payer electronically transfers the data directly. However, for standard commercial or mixed dual insurances, automated sharing is not guaranteed.

Most users on Reddit agree that providers are responsible for submitting the primary EOB and secondary claim manually or through a clearinghouse.

Does secondary insurance pay for copays?

Secondary insurance may cover a primary insurance copay, but it is not guaranteed and depends entirely on the rules of your secondary plan.

How Secondary Insurance Handles Copays

  • Coordination of Benefits (COB): This is the process your insurers use to figure out who pays first and second. Your Primary Insurance pays its share first, and then the remaining balance or leftover costs are sent to your secondary plan.
  • When it gets covered: In many cases, the secondary policy will pick up the remaining copay, coinsurance, or deductible left behind by the primary plan.
  • When it doesn't get covered: A secondary plan might not pay the copay if it has a "non-duplication" clause, enforces its own deductible first, or if the total payout hits the secondary plan's allowed limit for that service. You could still owe the copay out of pocket.

Best Practices

  • Check the EOB: Wait for the Explanation of Benefits (EOB) from both your primary and secondary insurance companies to see what was actually paid before paying a bill.
  • Network Status: Ensure your doctor is in-network for both insurance plans, as out-of-network rules can cause secondary coverage to deny claims entirely.

How does secondary insurance coverage work?

Secondary insurance coverage works by paying for medical costs that your primary insurance leaves behind, following a process called Coordination of Benefits (COB).

How the Process Works

  • Primary billing: Your doctor or hospital sends the bill to your primary insurance company first.
  • Primary payment: The primary plan pays its share of the claim based on your policy limits.
  • Explanation of Benefits (EOB): The primary insurer sends an EOB document showing what they paid and what balance remains.
  • Secondary submission: The claim or EOB is then sent to your secondary insurance plan.
  • Secondary payment: The secondary plan reviews the remaining balance (such as deductibles, copays, or coinsurance) and pays its portion according to its own rules.

Key Rules to Know

  • No double profit: Secondary insurance does not mean you get paid twice for the same bill. The combined payout from both plans cannot exceed 100% of the total medical cost.
  • Fixed order: You cannot choose which plan goes first. Industry rules and laws decide which policy is primary and which is secondary. For example, your own employer-sponsored plan is always primary over a plan you have as a dependent on your spouse's policy.
  • Out-of-pocket costs: Having a secondary plan does not guarantee that 100% of your bill will be paid. You may still owe copays or costs not covered by either policy. You also may need to satisfy the deductibles for both plans depending on their specific guidelines.

Learning How Medicare Works with a Secondary Insurance

9 related questions found

How is secondary insurance billed?

Secondary insurance is billed sequentially after the primary insurance company has fully processed the claim and issued an Explanation of Benefits (EOB).

The Step-by-Step Billing Process

  • Verify Coverage: Collect and verify both primary and secondary insurance information during patient intake. Ensure the Coordination of Benefits (COB) is established with the insurance companies.
  • Bill Primary First: Submit the initial medical claim to the primary insurance carrier for the full amount.
  • Receive the Primary EOB: Wait for the primary insurer to adjudicate the claim and provide an Explanation of Benefits (EOB). This document shows what the primary paid, adjusted, or applied to deductibles.
  • Submit Secondary Claim: File the claim to the secondary insurance carrier. You must include a copy of the primary insurer's EOB and primary payment details (either attached on paper or entered electronically).
  • Resolve Remaining Balance: The secondary insurance pays its share according to its policy rules. Any final leftover balance (such as remaining copays or non-covered amounts) is then billed to the patient.

Can you bill secondary insurance if primary denies?

You can bill secondary insurance after a primary insurance denial only if the primary insurer processed the claim and the denial meets specific criteria.

When You Can Bill Secondary Insurance

  • Service not covered: The primary insurance denies the service because it is an excluded benefit, but the secondary plan covers it.
  • Primary deductible not met: The primary insurance denies or applies the charge to an unmet deductible, leaving a balance that the secondary plan may pay depending on its rules.
  • Out-of-network primary denial (conditional): Some secondary plans pay if the primary completely excludes a service, but many reject claims if the primary denied it solely because the provider was out-of-network.

When You Cannot Bill Secondary Insurance

  • Billing errors: If the primary denied the claim due to a coding error, missing modifier, or lack of pre-authorization, fix the error and resubmit to the primary instead of forwarding it to the secondary.
  • Non-covered matching rules: If the secondary plan also has a rule stating it does not cover services denied as non-covered or lacking medical necessity by the primary.

Steps to Submit a Secondary Claim

  1. Wait for the primary insurance to process the claim and issue an Explanation of Benefits (EOB).
  2. Include the primary insurer's EOB and the primary payment or denial code with the secondary claim.
  3. Submit the claim to the secondary payer following their specific Coordination of Benefits (COB) guidelines.

Do I have to tell my primary insurance about my secondary insurance?

Yes, you must tell your primary insurance about your secondary insurance so they can coordinate your benefits correctly.

Why You Must Tell Them

  • Coordination of Benefits (COB): Insurance companies use COB rules to decide which plan pays first and to make sure total payouts never go over 100% of the medical bill.
  • Correct Billing Order: Your medical providers and insurers need the complete picture to bill the primary payer first and the secondary payer second.
  • Avoiding Delays and Denials: If your primary insurance does not know about your other coverage, or if claims are submitted out of order, your claims can be delayed or rejected.

How It Works

  • Primary Payer: Pays up to its policy limits first.
  • Secondary Payer: Steps in to cover remaining out-of-pocket costs like deductibles or copayments only after the primary insurer processes the claim.
  • Updating Records: You should inform both your healthcare providers and your insurance companies whenever you add, change, or drop coverage. You can check official guidance like the Medicare Coordination of Benefits page if government plans are involved.

Will my secondary insurance pay if Medicare denies my claim?

Generally, secondary insurance or a Medigap (Medicare Supplement) plan will not pay if Medicare denies a claim.

Why Secondary Insurance Denies Claims

  • Approved Amount Rule: Secondary and supplemental plans are designed to pay the out-of-pocket costs (like coinsurance, copays, or deductibles) only on amounts that Medicare approves.
  • Following Medicare Guidelines: As noted by a consensus of users on Facebook Groups, most secondary policies match Medicare's coverage decisions. If Medicare does not cover or approve a service, the secondary insurer usually denies it too.
  • Mixed Opinions on Exceptions: On forums like Reddit, some users note that rare secondary policies with very broad coordination-of-benefits clauses might cover certain non-Medicare services, but this is uncommon.

When Secondary Insurance Might Still Pay

Your secondary insurance might pay only if Medicare's denial is a technical error rather than a true coverage denial.

  • Filing or Coding Mistakes: If Medicare denies the claim because of a missing modifier, wrong billing code, or lack of basic patient information, it is not a permanent rejection.
  • Resubmitting: Once your doctor fixes the error and Medicare processes and pays its share, your secondary insurance will step in to cover its designated portion.
  • Medical Necessity Denials: If Medicare denies the service because it is not considered medically necessary or is outside Medicare's defined benefits, your secondary plan will almost always refuse to pay as well.

When billing secondary insurance, which of the following is not true?

The correct answer option is "The secondary insurance is billed at the same time the primary insurance is."

Explanation:

  • ❌ Why it is NOT true (The Correct Answer): You cannot bill a secondary insurance plan simultaneously with the primary plan. Standard billing guidelines require you to bill the primary insurance first. You must then wait for the primary insurer to process the claim and issue an Explanation of Benefits (EOB). The remaining balance is only sent to the secondary insurance after the primary payment has been applied.
  • Why the other statements are true:
  • If a Medicare Administrative Contractor (MAC) automatically forwards a claim via a crossover process, a separate manual claim to the secondary insurance is not required.
  • Blocks 9a–d of the CMS-1500 form must be completed because they house the secondary insurance policyholder's details.
  • Block 30 ("Balance Due") must be completed to reflect the exact remaining amount left over after the primary insurance made its payment.