Any other coverage must be billed and adjudicated before Medicaid pays. Skipping that step produces a denial that reads like a coverage problem but is a sequencing problem — the patient is covered, and the claim simply went to the wrong payer first.
Medicaid pays after everyone else. Not as a preference — as a statutory position. If any other coverage exists, it must be billed and adjudicated before Medicaid will consider the claim.
What counts as other coverage
Commercial insurance, Medicare, workers compensation, auto liability and no-fault, and in some situations other government programs. If the patient has any of it, Medicaid is behind it.
Why the denial is confusing
The denial reads like a coverage problem. Staff check eligibility, confirm Medicaid is active, and resubmit — which produces the same denial, because the issue was never eligibility. Medicaid is active. It is simply not first.
The fix requires billing the primary, waiting for adjudication, and submitting to Medicaid with the primary's remittance attached. That is a different workflow, and it takes time the primary's filing window is also consuming.
Where it goes wrong at the front desk
- Patients frequently do not mention other coverage, especially a spouse's plan or an auto policy.
- Coverage that lapsed and restarted looks like no coverage in a quick check.
- Injuries that turn out to be work-related or auto-related are not identified as such at registration.
The practical rule
Ask about other coverage explicitly at every Medicaid encounter, and ask about work and auto injuries in those words. Then record the sequencing decision so the next person does not re-derive it. This category is preventable at intake and expensive downstream, which is the worst combination to leave to chance.
Ask the question that finds hidden coverage
"Do you have any other insurance, including through a spouse, a parent, an employer, or an accident claim?" is a better question than "do you have insurance", because patients answer the short version about their primary card only.
Auto and work injuries are the most commonly missed, and both are primary to Medicaid.
Watch the filing clock while you sequence
Billing the primary, waiting for adjudication and then rebilling Medicaid consumes weeks, and the Medicaid window has been running from the date of service throughout.
Start the primary claim immediately on discovery. A last-resort denial found at ninety days can leave too little runway to complete the sequence.
Keep the primary remittance
Medicaid generally requires evidence of the primary payer’s adjudication, not just an assertion. Attaching the remittance is what turns the rebill into a payable claim rather than a second denial.
Common questions
- What does payer of last resort mean?
- Medicaid pays only after every other liable payer has been billed and has adjudicated. That includes commercial insurance, Medicare, auto and workers compensation.
- Why did Medicaid deny when the patient is clearly eligible?
- Usually because other coverage exists on file and has not been billed first. The denial is about sequence, not about eligibility.
- What counts as other coverage?
- Commercial plans, Medicare, auto liability, workers compensation, and sometimes coverage through a non-custodial parent. Any of them makes Medicaid secondary.
- What if the patient says they have no other insurance?
- Medicaid may still hold coverage on file from a source the patient forgot or does not know about. The state record governs, so verify rather than relying on the answer at the desk.
- How do I fix a last-resort denial?
- Bill the primary payer, obtain their remittance, then rebill Medicaid with it attached. Watch the Medicaid filing window, which has been running the whole time.
Denials Piling Up?
We handle the revenue cycle end to end — coding by certified coders, claim submission, denial management and appeals, and A/R follow-up, with six reported numbers every month.