What are the most common denial reasons?
The most common denial reasons fall into six steps of a hospital claim: patient registration, authorization, clinical records, coding, price and submission deadline. At each step, a different error leads the health plan to refuse, fully or partially, payment for an item or a claim form.
This guide does not rank reasons from most to least frequent. ANS tracks the volume of denials by health plan but does not receive the reason for each one [6]. Market studies use their own data and classifications. So the order here follows the claim, from registration to submission. The frequency figures that matter are each hospital's own, as the section “How to find which reasons weigh most in your hospital” shows.
The overall picture is in the Hospital denial guide. The split into administrative, clinical and across-the-board denial is in Types of denial; the meaning of each message is in TISS denial codes.
Why group reasons by the step where they start?
Grouping by step shows who can prevent the denial. The table 38 code says what the health plan claimed; the step says where the error entered the claim and which team has to change its process.
Two practical effects:
- Prevention moves upstream. A denial for an expired authorization number is not fixed in billing; it is fixed in the authorization team, before the deadline.
- Appeals cost less. An error fixed at the step where it started never reaches the health plan and needs no appeal.
The six steps where a denial starts
- Registration: the member or plan identification does not match.
- Authorization: the care or the item goes beyond what was authorized.
- Clinical records: the medical record does not support what was billed.
- Coding and quantity: the item was coded or counted wrong, or billed twice.
- Price: the amount does not follow the contract, the price table or the invoice.
- Deadline: the claim arrives after the contract deadline or outside the submission standard.
Steps 1 to 5 have their own table 38 messages [1]. Step 6 depends mainly on the contract: Law 9,656/1998 (the Brazilian health plans law) requires the contract between health plan and provider to set billing and payment deadlines [7].
Cause and prevention table by step
This table is the core of the guide. The codes were checked on the official TUSS lookup platform, with a start date and no end date [1]; names are shortened. The grouping by step is editorial, not an official ANS classification.
| Step | Reason | Table 38 code [1] | Typical cause | Prevention | Owner |
|---|---|---|---|---|---|
| Registration | Invalid member ID or member not identified | 1001 — Invalid member ID number | Typo, old card, plan changed | Check eligibility at admission and keep the response with date and time | Front desk and admissions |
| Authorization | Expired authorization number | 1414 — Authorization number validity date expired | Stay or treatment ran past the authorization date with no new request | Expiry alert and extension request before the deadline | Authorization team |
| Authorization | Quantity above authorized | 3292 — Quantity above authorized | Days, sessions or supplies beyond what was approved | Compare use with the authorization during the stay and request more | Authorization team and nursing |
| Clinical records | Item not justified in the record | 3217 — No justification or insufficient justification | Order, progress note or report does not explain the use | Check orders and progress notes before closing; physician report for high-cost items | Medical and nursing staff |
| Clinical records | Clinical disagreement about necessity | 3040 — Clinical denial (specify) | Health plan auditor questions the indication or appropriateness | Complete clinical records and internal audit of high-risk cases | Physician and nurse auditors |
| Coding and quantity | Incompatible or incorrect quantity | 3190 — Quantity incompatible with procedure · 3191 — Incorrect quantity | Wrong unit, splitting, typo | System rule comparing quantity with procedure and order | Billing and pharmacy |
| Coding and quantity | Duplicate billing | 3209 — Duplicate item · 3232 — Duplicate claim for a period already billed in an interim claim | Item entered twice or overlapping interim claims | Duplicate block at entry and control of interim claim periods | Billing |
| Coding and quantity | Quantity above coverage | 3293 — Quantity above covered | Item beyond the plan's or contract's coverage limit | Contract coverage rules set up in the system | Billing and contracts |
| Price | Amount different from contract | 1705 — Amount billed too high · 1706 — Amount billed too low | Outdated price table or wrong contract version | Contract price table in force on the date of care loaded in the system, with start date | Contracts and billing |
| Price | Invoice mismatch or invalid amount | 3310 — Invoice amount does not match · 3311 — Invalid amount | Supply invoice differs from the amount billed | Check implant (OPME) and supply invoices before submission | Purchasing and billing |
| Deadline | Claim sent after the contract deadline | 3214 — Billing after the deadline set in the provider contract | Late closing, claim waiting for a document | Closing calendar per health plan and deadline alert | Billing and management |
Registration, authorization, coding and price errors are usually administrative denials; clinical records concentrate clinical denials. Running these checks on every claim before submission is covered in the Claim pre-audit guide.
Registration and authorization: reasons that start before care
Registration and authorization are the cheapest steps to fix, because the error has not become a claim yet. What changes the result is checking at the right time and keeping proof.
- Eligibility with proof. In the TISS standard (the ANS data exchange standard), the electronic eligibility check is optional, and a denial must state the reason [2]. When the health plan offers the check, the dated response is the proof for an appeal against a 1001 denial. See Eligibility verification.
- Authorization deadlines under control. The expired authorization number (1414) is typical of long stays and series of treatments. The prevention is an alert that fires before expiry. See Expired authorization number.
- Authorization tracked during care. Quantity above authorized (3292) appears when actual use exceeds what was approved and nobody asks for more. Comparing use and authorization during the stay avoids surprises at closing.
Clinical records: the reason that needs the medical record
Clinical records are the step where a denial can only be prevented with documentation. Message 3217 points to missing justification; 3040 is the clinical denial, whose official description asks the health plan to specify the reason [1].
Prevention depends on clinical staff, not billing: dated and signed orders, progress notes that explain each relevant item, and a physician report for high-cost supplies and drugs. RN 503/2022 (ANS Normative Resolution 503/2022, on contracts between health plans and providers) requires the contract to set out the administrative and clinical audit routine and the cases in which a denial may apply [3]. Knowing those cases in each contract helps decide what the record must show. The link between record and claim is covered in Clinical documentation for billing.
Coding, quantity and price: reasons that start at data entry
Coding, quantity and price are the steps where automated rules pay off most, because the check is objective.
- Duplicates (3209, 3232). They start with repeated entries or with an interim claim covering a period already billed. A system block and control of interim claim periods usually prevent them.
- Quantity (3190, 3191, 3293). It starts with a wrong unit or splitting. The rule compares quantity with the procedure and the order.
- Price (1705, 1706, 3310, 3311). It starts with an outdated table or the wrong contract version. The system must hold the price table in force on the date of care, with its start date, and supply invoices must match the amount billed.
Deadline: the reason that starts at closing
Deadline is the step where the denial comes from the calendar. Law 9,656/1998 requires the contract between health plan and provider to state billing and payment deadlines [7], and RN 503/2022 details what these contracts must contain [3]. The submission deadline is therefore the one in each health plan's contract.
Prevention is organizational: a closing calendar per health plan, alerts for claims waiting for documents, and batch submission in the current TISS version. Electronic billing is mandatory in the standard [2]. See Claim submission deadlines.
How to find which reasons weigh most in your hospital
The frequency that matters is the hospital's own. The claim review statement lists, for reviewed claims, only the denied items, each with its table 38 message [2]. With it, a hospital can build its internal ranking:
- Tag each denial by step, using this guide's table as a crosswalk.
- Add up by amount, not only by count. A few implant items may weigh more than many daily rates.
- Split by health plan. The same reason can be rare at one plan and recurring at another.
- Cross-check with appeal results. A reason with high reversal points to undue denial and goes to negotiation; a reason with low reversal points to an internal error and goes to prevention.
Industry figures help with scale, within their limits. At Anahp hospitals, initial denial was 15.93% of amounts receivable from health plans in 2025, and accepted denial was 1.72% of gross revenue from health plans [4]. The two figures have different bases and should not be divided by each other. The 2026 Panorama do Ciclo de Receita (Revenue Cycle Overview) by ZG Soluções, based on the company's client data and not comparable to Anahp, attributed 67.9% of the denied amount to preventable failures [5]. More figures are in Industry data.
What we see in operations
At Accrua, we use the same logic as this guide: each denial is tied to the step where it started, from registration to deadline. When we read the history of claims the hospital has already submitted, we classify each TUSS table 38 reason by step, by health plan and by item, and show claim by claim where the opportunity is.
That reading splits denials into two groups. Some come from internal errors and are solved at the source, with whoever registers, authorizes, documents or posts charges. Others tend to be overturned on appeal, a sign that the problem lies in the health plan's interpretation or in the contract, not in the hospital.
Accrua OS reads every health plan claim before submission, not a sample, and checks each item against the contract, the current price table, the authorization rule and that health plan's denial history. What we learn from one appeal becomes a check on the next claim.
Where to start
- Pull the claim review statements for the last 12 months and tag each denial by step.
- Rank the steps by denied amount, split by health plan.
- Name an owner for each step, as in this guide's table.
- Create a prevention rule for the two steps with the highest amounts and measure initial denial before and after.
- Take high-reversal reasons to negotiation, since they point to undue denial by the health plan.