Timely filing · ACA marketplace (Illinois)
Ambetter timely filing limit
Short answer
The Ambetter timely filing limit in Illinois is 180 calendar days from the date of service for participating providers and 90 calendar days for non-participating providers, counted to the day Ambetter receives the claim. Observation and inpatient stays count from the discharge date. When another plan is primary, the same 180 or 90 days run from the primary payer's EOP date.
Corrected claims, requests for reconsideration and claim disputes must arrive within 180 days of the original EOP or denial, and the dispute table limits non-participating providers to 90 days. Ambetter of Illinois is underwritten by Celtic Insurance Company. Compare other payers in the timely filing limits table.
Last reviewed by the Remitwright billing team. Editorial policy
The windows
- Initial claim
- 180 calendar days from the date of service for participating providers; 90 calendar days for non-participating providers1
- Counted from
- The date of service to the date Ambetter receives the claim, or the discharge date for observation and inpatient stays. Secondary claims count from the primary payer's EOP date. Reconsiderations and disputes count from the date of Ambetter's EOP.
- Appeal
- 180 calendar days from the date of Ambetter's EOP for a request for reconsideration or a claim dispute; 90 calendar days for non-participating providers
- Corrected claim
- Corrected claims must be received within 180 days of the date of the original explanation of payment or denial. After that, Ambetter upholds the prior processing unless you document one of its qualifying circumstances.
- Verified
- , against the payer document in the sources
Your participation agreement can set a different window. Where the contract and the manual disagree, the contract applies.
A visit on Monday, March 2, 2026
Counting 180 days forward from a date of service of Monday, March 2, 2026 gives Saturday, August 29, 2026. That is the last day to file under the first limit shown above; a claim filed after it is outside the window unless one of the exceptions below applies.
Exceptions the payer allows
Another plan paid first
When Ambetter is secondary, participating providers have 180 calendar days and non-participating providers 90 calendar days from the primary payer's EOP date to the day Ambetter receives the claim. Send the COB data in the electronic claim so the primary payment is visible.
Catastrophe, disaster or a payer error
A late corrected claim, reconsideration or dispute can be considered when a catastrophic event substantially interfered with your business, when a natural disaster or mechanical failure damaged your office or records, or when administrative delays or errors by Ambetter or a federal or state regulator caused the delay. Documentation of the circumstance has to come with the request.
The member did not show coverage
If the member was eligible but you did not know it at the time of service, Ambetter considers the late request only when your records show the member refused or was physically unable to give an ID card or coverage details, you kept pursuing the patient for payment until eligibility came to light, and you had not filed a claim for that member before.
What counts as proof of timely filing
- The 277CA claim acknowledgement returned for the original electronic claim
- The Ambetter Claim Audit Report for the original submission, which with the 277CA is the only claim-level acknowledgement of receipt
- For a secondary claim, the primary payer's EOP showing the date that starts the COB window
- For a late request, documents that support the qualifying circumstance, such as records showing the member could not or would not present an ID card
Notes for billers
- Claims that fail the clearinghouse or plan edits are rejected without being recognized as received by Ambetter. Review your acceptance and rejection reports daily, correct the claim and resubmit it as an original claim inside the filing deadline.
- The order of review is fixed. A corrected claim changes the original claim. A request for reconsideration says you disagree with the outcome. A claim dispute is only for an unsatisfactory reconsideration result, and a dispute form filed with no reconsideration on record is handled as a reconsideration. Ambetter resolves disputes within 30 calendar days.
- Send corrected claims through the secure provider portal, through a clearinghouse with claim frequency code 7 and the original claim number, or on red and white paper forms with the original claim number in Box 22 of the CMS-1500 or field 64 of the UB-04. Handwritten corrected claims are rejected up front.
- Ambetter's payer ID is 68069. Paper claims go to Ambetter, Attn: Claims, P.O. Box 5010, Farmington, MO 63640-5010. Ambetter does not accept handwritten, faxed or replicated claim forms.
- Ambetter's payment, less the member's copay, coinsurance or deductible, is payment in full. You cannot bill the member for the difference between your charge and the contracted rate.
- The figures on this page come from Ambetter of Illinois documents and apply to Ambetter of Illinois claims. Ambetter's guides tell you to check the member ID card for the right authorization and claims submission process before you bill.
FAQ
Questions about Ambetter deadlines
What is the Ambetter timely filing limit in Illinois?
How long do I have to dispute an Ambetter claim decision?
Does a corrected claim restart the Ambetter filing clock?
How is timely filing counted when Ambetter is the secondary payer?
What proves an Ambetter claim was filed on time?
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