Claim Rejection vs Denial: How to Tell Which One You Have and What to Do Next

What a rejected claim is

A rejected claim is one the payer refused to take in. It failed a check at the front door, before anyone decided whether to pay it. It usually gets no claim number and never reaches the payer’s claims system. Most rejections come back on an acknowledgment report. Some payers return an unprocessable claim on the remittance instead, marked with remark code MA130, which says to submit a new claim with complete, correct information.

Medicare’s claims manual spells out the rule. Claims that fail basic format or completion requirements “are not considered as received” and may be rejected. A rejected claim does not count as received until you resubmit it as a corrected, complete claim. A claim returned as unprocessable “does not meet the criteria to be considered as a claim, is not denied,” and has no appeal rights.

Indiana and Texas Medicaid work the same way. Indiana’s claim submission module (version 8.5, February 24, 2026) says electronic claims that fail HIPAA compliance checks are rejected before processing, reported on a 999 acknowledgment, and never enter the state’s claims system. Accepted electronic claims then get a Claim ID. Texas Medicaid considers a claim for payment only after it shows as accepted on the Claim Response report in the 27S batch response file, and rejected claims must be corrected and sent again.

Common reasons a NEMT claim is rejected:

• The rider does not match. Texas lists this first: the name, date of birth, sex, and nine-digit Medicaid number must exactly match the state’s eligibility record.
• A missing or invalid identifier, such as your NPI, the rider’s ID, or the taxonomy code. Texas may reject claims sent without the taxonomy code.
• A broken file. A wrong format rejects the claim, and sometimes the whole file.
• You are not enrolled yet. Texas rejects a new provider’s claims until enrollment is complete.

What a denied claim is

A denied claim made it in. The payer accepted it, ran it through its payment rules, and decided not to pay all or part of it. A denial has a claim number, shows on your remittance advice, and carries a group code and a reason code that say why.

Indiana’s module describes the split plainly. A claim that follows the format and the program’s policy rules is paid. One that breaks the format or policy rules is denied. Weekly, the state sends an 835 electronic remittance with the paid and denied claims. See 835 ERA for how that file reads.

Typical NEMT denial reasons, with their national reason codes:

Reason code	What it says	Common NEMT cause
177	Patient has not met the required eligibility requirements	The rider’s coverage lapsed on the date of service
197	Precertification or authorization absent	No trip or authorization number on the claim
18	Exact duplicate claim or service	The same trip billed twice
182	Procedure modifier was invalid on the date of service	An old or unlisted modifier
29	The time limit for filing has expired	Sent after the payer’s deadline
109	Not covered by this payer	Billed to the state when a health plan or broker owed it

For the full list and the fix for each, see claim adjustment reason codes and NEMT claim denials.

How to tell which one you have

The report it comes on usually tells you.

	Rejection	Denial
Where it shows up	A TA1 or 999 for a file problem, a 277CA for one claim, or the payer’s rejection report	The remittance advice or 835
Claim number	Usually none	Yes
Status codes	277CA category A3, A6, A7, or A8	277 category F2, “Finalized/Denial.” In the 835, claim status code 4
Received for filing deadlines	No, not until you send a clean claim	Yes
Appeal rights	None	Yes, within your payer’s window
What you send	A new, fixed claim	A corrected claim or an appeal

The X12 category codes on a 277CA make the line clear. A1 means received but not yet accepted, A2 means accepted into the payer’s system, and A3 means “returned as unprocessable,” rejected and never entered. A6, A7, and A8 are rejections for missing information, invalid information, or two fields that do not agree.

A third status sits between the two. A pended claim was accepted but is on hold for review. It shows a P category code on a claim status check and ends paid or denied on a later remittance. See how to check Medicaid claim status.

Why the difference matters for filing deadlines

Federal rule 42 CFR 447.45 requires Medicaid providers to submit every claim within 12 months of the date of service, and states can set shorter limits. A rejected claim does not stop that clock, because it was never received. A denied claim was received, so if it arrived on time it met the filing deadline, even though it was not paid.

Texas shows how tight this gets. As of September 2026, TMHP, which processes Texas Medicaid claims, must receive most in-state claims within 95 days of the date of service, and appeals within 120 days of the date on the Remittance and Status (R&S) report that listed the claim. Texas keeps a narrow door open for rejections. A new provider whose claims are rejected until enrollment finishes may use the rejection report as proof of meeting the 365-day federal deadline in an appeal. Treat that as an exception, not a plan. See timely filing limit for other states.

What to do with each one

For a rejection:

1. Read your 999 and 277CA reports every day you send claims. A rejection sitting unread still counts against your deadline.
2. Find the field the report names, such as the member ID or date of birth, and compare it with the eligibility check for that date.
3. Fix the trip record or your billing setup so the next claim does not fail the same way.
4. Send the claim again as a new claim. There is no payer claim number to correct, because the first one never entered the system.
5. Confirm it now shows as accepted on the next acknowledgment.

For a denial:

1. Read the group code, reason code, and any remark code on the remittance.
2. Decide whether the claim was wrong or the decision was. A wrong code, modifier, or mileage calls for a corrected claim. A decision you disagree with calls for an appeal.
3. Send a corrected or replacement claim the way your payer asks, usually with the original claim number. See corrected NEMT claims.
4. For an appeal, gather the trip log, authorization, and signatures, and file inside the payer’s window. See how to appeal a denied Medicaid claim.
5. Do not resend a denied claim as brand new unless the payer says to, or it can deny again as a duplicate.