CO 18 Denial Code- Exact Duplicate Claims or Services

More than 10% of the denial rate is commonly reported in one in every three hospitals. Having a high denial rate is considered as harmful when denials are considered. The main cause of the increase in the denial rate is the pandemic. This has concluded in healthcare organisation gaining the chance to declare that insurance organisation is not accepting initial. But here lies the question of where the code is, which has come back when an insurance organisation denies a claim without explanation.

It has become essential during this situation to make denials of the healthcare organization more manageable by translating insurance organization and built-in workflows. Therefore, it has become essential to assist in clarifying the purpose of denial codes by explaining the method to avoid and overturn them. Moreover, one of the well-known codes is Co 18 denial code, which is used almost everywhere and is essential to understand.

Table of Contents

What is Co 18 denial code?

The CO 18 denial code is a type of error that can occur when submitting claims to Medicare. It is related to duplicate claims, which can result in a loss of revenue for your practice and potential penalties from the Medicare administrative contractor. To avoid this type of denial, it is important to ensure that all claims have accurate information such as provider number, date of service, HIC number, procedure code, billed amount, type of service, place of service, and so on.

If a CO 18 denial code does occur, it is recommended to review the claim and make any necessary corrections before resubmitting it. Overall, it’s important to be familiar with the CO 18 denial code and understand how to prevent and address it to maintain a smooth billing process.

How to handle co 18 denial code?

There are different causes for forming the Co 18 denial code. So, it is essential to consider those causes to handle Co 18 denial code and avoid them.

The same claim is submitted more than once

Though this is done by mistake, it could be costly, so it is important to handle and avoid this situation of the Co 18 denial code, as Medicare or insurance companies will only pay once. The insurance organisation will only pass judgment for the first and original claim and ignore or deny the remaining claims. It is the responsibility of the health care provider to ensure by checking the insurance organisation about the process towards payment of the original claim, or it’s denied.

The corrected claim has been resubmitted.

If a healthcare provider has resubmitted a corrected claim without specifying that the claim has been corrected may end up for the same service or claim. You have to make sure whenever a claim has been corrected to specify the claim as a corrected claim by mentioning the claim# on the claim form to method the claim, which is corrected appropriately. This will allow you to avoid Co 18 denial code.

On the same date, the same service is performed by another employee.

Sometimes two different healthcare provider provides service to the same client on the same day. This may result in one provider receiving payment before calm, whereas other claims provided by another provider will get denied. In such situations, the provider whose claim has been denied has to get clarification from the client about the service provided, and if there is an end, the claim will be reprocessed. You must appeal the claim and give supporting documents if they do not want to send the claim back for reprocessing.

The same provider performs the same service multiple times.

If the same provider provides the same service multiple times a day, the claim will be explained as if it was not planned with a correct modifier. The claim will be processed only for the first claim, whereas the remaining claims will be considered the same service or claims. The second and another claim done after the first claim should be append with the correct modifier. The provider will be required to appeal and provide documentation if it’s denied again.

One provider performed the same service bilaterally.

Suppose the same provider performs the same service bilaterally. This will form Co 18 denial code. In that case, it means that more than one patient’s claim has been submitted without the correct modifier, as one of those claims may receive payment, and the other could be denied as a duplicate claim. To overcome or handle this situation provider will require to bill the correct modifier to specify the method was performed bilaterally.

Many healthcare faces denial issues, due to which they have to face much loss. These issues are mostly faced because of providing duplicate claims and services, also referred to as Co 18 denial code. A healthcare provider can easily handle and avoid these issues by adopting a few additional steps or changing their working method. However, handling Co 18 denial code is essential under the cause, among which a few have been explained above. Later, the method of handling and avoiding those Co 18 denial codes has been properly explained, which are convenient to adopt by the service providers in health care.


Q1. What is Co 18 medical billing?

Ans. Co 18 is used for the same service and claims provided by health care providers. Co 18 medical billing comes under Co 18 denial code.

Q2. What could be the cause of the duplicate claim?

Ans. There are many causes of duplicate claims or claims to be denied (Co 18 denial code). But one of the main causes recognised is healthcare providers providing the same service more than once on the same day.

Q3. Can an insurance organisation reject the claim after a few years?

Ans. A claim must be accepted by the insurance organization after three years of policy commencement, even though there is non-disclosure or misstatement by the policyholder.

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