Reasons for hospital claim denials: how to identify and resolve them

A claim denial is the full or partial refusal by a health plan to pay for a service the hospital, clinic or laboratory has already delivered. Every denied claim means withheld revenue, a longer payment timeline and rework for the billing team.

For hospital managers, understanding the most frequent causes of denials is the first step to reducing losses and regaining financial predictability. Identifying the right code, classifying the type of occurrence and acting within contractual deadlines make a direct difference to the month’s results.

This article presents the most common reasons for denials based on the TISS standard (Supplementary Health Information Exchange) of the ANS (Brazil’s National Supplementary Health Agency), and explains in practical terms how the billing team should handle each one.

What a claim denial is and why it happens

A denial occurs when the health plan disputes an item on the hospital claim. The refusal can be full, when the entire charge is denied, or partial, when only some items or amounts are denied.

The reasons for a denial vary: they can involve filling errors, missing mandatory documentation, clinical incompatibility, use of expired authorization codes or charges above the contracted amount.

The TISS standard, regulated by the ANS through Normative Resolution No. 305/2012, which sets the requirements for the electronic exchange of information between providers and payers, organizes these occurrences into codes that identify exactly the reason for the refusal.

Although the codes are standardized, how they are applied in practice varies across payers. Some use their own lists or internal rules that differ from the ANS standard, which reinforces the need for the hospital to monitor its contracts continuously.

How to identify a denial and find its code

Identification starts with the payer’s official notice. It can arrive through different channels: a denial report sent by email, a financial statement, the payer’s online portal or an XML file in the TISS standard.

This notice contains four pieces of information essential to the billing team’s work:

• the denial code;
• the reason for the refusal according to the TISS standard;
• the item or procedure affected;
• guidance for appeal, when provided for in the contract.

To learn more about the concept and types of denials, read the article Claim denials: what they are and how to prevent them.

Main causes of claim denials in the TISS standard

Below are the denial codes most frequently seen at private healthcare institutions, with practical guidance for each one.

Denial code 1702: duplicate procedure billing

It occurs when the same procedure is billed more than once on the same day by the same professional. It can arise from a failure in the recording system or from forms submitted twice.

To prevent it: enter the exact date and time for every procedure; when there are separate forms for the same item, justify the technical need; review requests with identical codes before submitting the batch.

Denial code 1818: procedure performed without prior authorization

Many payers require authorization before certain procedures. If that authorization is missing, denial code 1818 is applied. Process errors, such as authorization codes that are incorrect or already expired at the time of care, also trigger this occurrence.

To prevent it: check the authorization requirements for each contracted plan; confirm that the authorization code is active and valid before the procedure starts; document the internal pre‑check processes.

Denial code 1414: expired authorization code

The authorization code has an expiration date set by the payer. If the procedure is performed outside that period, the denial is automatic. Changes to the surgery or admission date are the most common causes.

To prevent it: monitor the expiration date of each active authorization code; request revalidation if the schedule changes; record the changes in the medical record and in the authorization request.

Denial code 1816: charge incompatible with the clinical course

It indicates that the procedure billed is not compatible with the documented clinical condition or that the justification presented is not enough to support the charge. Missing medical reports and the payer’s coverage limits can also trigger this denial.

A practical example: a request for 40 variations of a RAST test when the plan covers only 30. In this case, the excess charge is denied as incompatible with the contract.

To prevent it: attach reports, clinical justifications and care protocols to the forms; check coverage limits before performing the procedure; align with the attending physician whenever there is any inconsistency between the prescription and the plan’s rules.

Denial code 1707: inconsistency in the pricing table

It relates to credentialing problems, a mismatch between the contract table and the code billed, or a filling error in the batch submitted. It can occur when the patient’s plan was registered incorrectly at admission.

To prevent it: review the contract and the current price table before submission; check billing codes against the updated TUSS table; confirm that the plan was correctly identified and assigned at admission.

Denial code 3052: incomplete, incorrect or missing documentation

One of the most frequent denials in hospital billing. It can be triggered by a missing physician order, a missing plan member signature, blank dates, documents sent outside the required standard or a copy sent when the payer requires the original.

To prevent it: know each payer’s specific documentation rules; implement checklists of mandatory documents by type of care; digitize and store supporting documents in an organized way, ensuring traceability.

Denial code 1817: procedure already included in the main procedure

When an item billed is considered an integral part of the main procedure, the payer denies it on the grounds that there is no room for a separate charge. This is common in surgeries with multiple operative stages or in procedure packages.

To prevent it: check compatibilities in the ANS list of procedures and in the payer’s contract; confirm the technical details with the attending physician; review packages and allowed combinations before submitting the claim.

Denial code 1714: service amount above the table price

It occurs when the amount billed does not match what was agreed in the contract. It may indicate a failure to update the table in the system, an error selecting the plan at the time of care or a contractual adjustment not yet applied.

To prevent it: review payment statements regularly; check that contractual adjustments have actually been applied in the system; confirm that the care was recorded under the correct plan. For more details on this specific code, read the article Denial code 1714: what are the best ways to prevent it?.

Denial code 1018: plan member’s employer suspended or excluded

It happens when the patient’s employer-sponsored contract is suspended on the date of care. The hospital delivers the service without noticing that coverage is not in force, and payment is refused.

To prevent it: check the plan member’s eligibility at admission, directly with the payer; make sure the date of care is correctly recorded in the system.

Denial code 1010: missing signature of the policyholder or guardian

One of the simplest denials and, at the same time, one of the most recurrent. A missing signature on the discharge or authorization document is enough to trigger the refusal.

To prevent it: check the signature of the patient or guardian at discharge or when care is completed; implement digital signature protocols when the payer accepts that format.

Denial code 1709: item billed without a medical prescription

Applied when medications, materials or procedures billed do not appear in the medical prescription attached to the claim. Billing items outside the prescription is one of the main causes of denials in nursing.

To prevent it: bill only what is documented in the prescription; make sure the nursing team validates prescriptions before the claim is closed; attach legible and complete documentation to the billing process.

What to do when you receive a denial

When a denial is identified, the provider can file an administrative appeal with the payer within the deadlines set in the contract. The process follows defined steps and requires rigorous document organization.

1. Identify the code and the denied item in the notice.

2. Gather supporting documents: reports, physician orders, protocols, system screenshots.

3. Prepare a clear and objective technical justification.

4. Submit the appeal through the payer’s portal or the TISS system.

5. Track the response and record the outcome to analyze recurrence.

Appealing consistently can recover significant amounts and reveal error patterns that, once corrected, reduce future denials. See the complete step by step in the article Denial appeals: how to control and recover amounts.

How to reduce denials systematically

Preventing denials requires an approach that combines processes, training and technology. One-off actions resolve isolated occurrences, but only structured management can reduce the overall denial rate over time.

On the process side: implementing checklists by type of care, establishing eligibility protocols at admission and creating internal audit routines before claims are submitted are measures with fast, measurable returns.

On the people side: training the billing team to know each payer’s rules, including individual contracts and their particularities, reduces systematic errors that repeat month after month.

On the technology side: artificial intelligence makes it possible to automatically cross-check clinical data against each payer’s rules before the claim is submitted. This anticipates inconsistencies, reduces rework and speeds up the closing of the revenue cycle.

Artificial intelligence helps fight claim denials

Most of the denials listed in this article originate in preventable failures: incomplete documentation, expired authorization codes, charges outside the table or items without a prescription. This means that a large share of hospital billing losses can be eliminated with more rigorous processes and the right tools.

Rivio uses artificial intelligence to manage the entire hospital revenue cycle. The platform analyzes clinical records, cross-checks information against hospital claims, identifies inconsistencies before submission and automates the denial appeal process. The result is faster billing, fewer losses and greater financial predictability for the hospital.

FAQ: frequently asked questions about hospital claim denials

What is the difference between a technical denial and an administrative denial?

A technical denial questions the clinical appropriateness of the procedure billed, such as incompatibility with the diagnosis or a missing report. An administrative denial stems from process errors, such as incomplete documentation, an expired authorization code or duplicate billing.

Is the hospital required to accept the payer’s denial?

No. The provider has the right to file an administrative appeal within the contractual deadlines. If the appeal is rejected, it can escalate to higher levels or seek mediation through the ANS.

What is the deadline to appeal a denial?

Deadlines vary according to the contract between the hospital and the payer. In general, they range from 30 to 90 days after the notice. That is why monitoring payment statements frequently is essential to avoid missing the appeal window.

How does artificial intelligence help reduce denials?

AI platforms can audit claims in real time, identify inconsistencies before submission, check compatibility between diagnosis and procedure and automate the generation of appeals. This reduces rework and increases the claim approval rate.

What is the TISS standard and how does it relate to denials?

TISS is the standard defined by the ANS for the electronic exchange of information between providers and health plans. It organizes denial codes and the submission formats for forms, reports and appeals. Knowing the TISS standard is essential to understanding the reasons for refusal and structuring efficient responses.