Ambulatory Surgery Center Billing Guidelines

Ambulatory Surgery Center Billing Guidelines

Starting an ambulatory surgery clinic has always been a complex task that requires attention to detail. Those who don’t have any prior experience in the medical field may get lost in the sea of information and requirements circulating this business. That’s why this article will focus on explaining the ambulatory surgery center billing guidelines and what they’re made of.

With its help, you’ll be able to tell apart the difference between ASC billing and other healthcare practices and discover its unique features. Moreover, you’ll understand its importance, key components, and how to use it in your business properly. By being aware of all the requirements, you’ll avoid future problems and ensure the ASC runs smoothly.

Continue reading to discover all there is to know about medical billing and coding guidelines and why they’re so important.

Understanding Ambulatory Surgery Center Billing

Understanding ambulatory surgery center billing and coding requires thorough research and experience. Since these facilities specialize in outpatient procedures, they are more extensive than the ones performed at a typical office. However, since they don’t require hospital stays, they have their own specific billing procedure.

In order for the ASC services to be paid, any procedures done must be determined as a medical necessity. That being said, the two main factors that affect the total cost of the medical procedure are:

  1. The physicians’ professional services,
  2. The services furnished by the facility (equipment, surgical supplies, nursing).

Any ASC surgery claims are filed through Medicare with HCFA 1500 or 837P forms. Furthermore, there are annual ASC Payment System updates set by the CMS to maintain budget neutrality. They also make a geographic payment adjustment using pre-reclassified hospital wage index values.

Since there are many complex elements that medical billing consists of, you can always hire an ambulatory surgery center consultant service to help you out. The professional consultant will happily guide you through the process while explaining each step.

Understanding Ambulatory Surgery Center Billing
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The key differences from other healthcare practices

Even though there are some similarities, ASC medical coding and billing differs from other regular physician billing in several ways. But this doesn’t mean you must learn an entirely new set of codes since they mostly use the same billing techniques and coding guidelines. 

First, ambulatory surgery centers usually incorporate every medical specialty in a single place. So this type of coding system doesn’t have to focus on a specific medical specialty, as well as procedures, services, or diagnoses. On the other hand, in physician medical billing, you must focus on several highly specialized guidelines to get reimbursed.

The second important difference is that an ASC must do their billing through the CMS-1500 claim form. It represents a standard claim form that non-institutional providers or suppliers use. Thus, it is not required as a facility claim form.

Lastly, an ASC can only provide services to patients a primary care physician has already diagnosed. The patient must have a necessary medical procedure for the ASC to be reimbursed. Even though ASCs offer high-quality services at an affordable cost, the patient can still refuse to get treated at the facility.

Importance of Accurate ASC Coding and Documentation 

Now that you know the difference between ASC billing and other healthcare facilities, you should also understand its importance. Accurate documentation and coding can make a world of difference in an ASC. They affect both the workflow and the proper ambulatory surgery center management. Furthermore, they act as a solid foundation for effective ASC billing and compliance when properly done.

Regarding the workflow, if clinical documentation doesn’t meet the coding compliance, it might slow the physicians’ reaction time. Instead of focusing their attention on the patients, the surgeons will have to divert it to verify the accuracy of the notes. 

These documents hold important information about the acuity of the patient in question and how they should be treated. Thus, by providing accurate documentation from the start, you’ll preserve patient face-time and optimize the efficiency of a revenue cycle process.

On the other hand, accurate coding will ensure you receive the appropriate reimbursement for the services. As mentioned, this process involves assigning standardized codes to procedures, services, and diagnoses. This ensures the claims are billed properly and reduces the risk of denials and underpayment.

What should ASC documentation include

Accurate documentation ensures that all the needed information and details are recorded. This leads to proper coding, billing, and reimbursement. The three most important aspects that should be documented are:

Patient medical history and information

It focuses on demographics, consent forms, and insurance details. It helps verify patient eligibility, ensures compliance with privacy regulations, and helps obtain the required pre-authorization.

Patient medical history and information
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Surgical procedure

This procedure must be documented in detail to ensure proper billing. Some of the most important specifics are the techniques used and the complications encountered. 

Furthermore, you should also mention any used equipment. With accurate documentation, you can assign the appropriate CPT (Current Procedural Terminology) codes. This way, you’ll further support medical necessities.

Post-operative care

This type of documentation should include details about the care after the procedure. This includes the administered medications, pain management, and follow-up instructions. It highly assists in monitoring patient outcomes. Furthermore, it ensures accurate billing for all rendered services. 

What should ASC coding include

To conduct accurate coding for an ASC, you should remember several considerations. These include the following:

CPT and HCPCS codes

By choosing the appropriate codes, it’s easier to determine the nature and complexity of the services and procedures performed. You should always follow the most recent official coding guidelines. By keeping up with their updates, you further ensure accuracy.

Diagnosis coding

Assigning the correct diagnosis codes for your patient’s medical condition is crucial for reimbursement and medical necessity. It’s easier to define the correct codes from the ICD code set when combined with the proper documentation. 


These additional codes provide extra information about your services. They also impact reimbursement and compliance. It’s essential first to include the procedure with the highest RVU (relative value unit). This way, you’ll prioritize listing the highest-paying services first and then adding the ones with a lower RVU.

Overview of Ambulatory Surgery Center Billing Guidelines

Since the CMS does annual updates to the ASC payment system, it’s important to keep up to date with it. But one of the most important rules you should know is that Medicare doesn’t allow the execution of just any surgical procedure in these settings. To ensure the safety of the patients, there’s a list of approved services that can be performed in an ASC. This way, they ensure that the patient won’t require an overnight stay and will get the best possible care.

The approved procedures that can be executed in an ASC are determined based on the following criteria:

  • The procedure should not be of an emergency nature or life-threatening
  • The procedure could not be performed in a physician’s office safely
  • The procedure is elective
  • The procedure is urgent
  • The procedure doesn’t involve major blood vessels that might lead to blood loss

Key Components of ASC Billing 

When dealing with ASC billing, there are several key components you should be aware of. These include:

  • Procedure coding
  • Modifier usage
  • Claim submission
  • Reimbursement procedures

Procedure coding

So what is ambulatory coding, and what purpose does it have in the ambulatory surgery center billing process? The ASC coding guidelines ambulatory are used to describe each provided service tidily. In most cases, ASC uses a combination of physician and hospital billing. Thus, they fall under the CPT and HCPCS level codes

These codes stand for Current Procedural Terminology and Healthcare Common Procedure Coding System. They both represent a uniform language for healthcare providers and doctors. Furthermore, these standardized codes represent medical procedures, services, supplies, and products. With their help, it’s easier to organize reporting and increase efficiency and accuracy. 

Some insurance carriers also approve using ICD-10 procedure codes common in most hospitals. This stands for the tenth revision of the International Classification of Diseases. It’s made of codes for diseases, abnormal findings, signs and symptoms, and external injury causes. 

Procedure coding
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Modifier usage

Modifiers are additional two-digit numbers or letters. They are added to a procedure code to show that it has been altered. Furthermore, they can be used both for Medicare and for other payors. But they may differ based on the specific requirements. Failing to use the proper modifiers based on the payor’s needs may lead to denials or improperly paid cause claims.

Furthermore, many people turn to modifiers when a patient needs another procedure after the primary one. This is usually within a day but may vary depending on the payor. It’s called the Global Period or Postoperative period and may last from 24 to 72 hours.

When using modifiers, you should mention the ones that affect the payment before using the informational ones. Additionally, in some procedures, you should always include modifiers representing which side of the body the surgery has been done on. They are represented with -RT and -LT, depicting the right and left sides of the body. These modifiers are most common in orthopedics, ophthalmology, and podiatry.

Commonly used modifiers and their meaning

These extra codes can be used in two ways. First, they can describe a surgical process in detail. Secondly, they can give more information about the service. 

That’s why they’re commonly separated into procedural and informational modifiers. To better understand their use and meaning, take the time to review both of them carefully.

Procedural modifiers

The common procedural modifiers you should be aware of are the following:

  • Modifier 50 – represents a bilateral procedure that must be performed on both sides of the body,
  • Modifier 51 – stands for multiple procedures done in a single session,
  • Modifier 52 – indicates reduced services based on the physician’s discretion; using it may lead to lower reimbursement rates,
  • Modifier 58 – staged or related service by the same physician during a postoperative period,
  • Modifier 59 – represents a distinct procedural service; it also indicates that a separate procedure was performed on the same date as a different surgery,
  • Modifier 73 – discontinued ASC procedure before the administration of anesthesia,
  • Modifier 74 – discontinued ASC procedure after the administration of anesthesia,
  • Modifier 76 – indicates a repeated service or procedure done by the same physician,
  • Modifier 77 – indicates a repeated service or procedure done by a different physician,
  • Modifier 78 – stands for returning to the OR for a related surgical procedure during a postoperative period,
  • Modifier 79 – indicates an unrelated surgical procedure done during the postoperative period.
Informational modifiers

After reviewing the procedural modifiers, it’s also beneficial to discover the meaning behind the informational ones. When dealing with ASC billing, the informational modifiers that most commonly appear are the following:

  • SG Modifier – used to mention a surgery center; it must be included in forms from 2007 and before; when using this modifier, you must always mention it before the others,
  • GY Modifier – stands for a non-covered procedure; it is used to let the payor know that you’re aware that they won’t cover the service,
  • FB Modifier – indicates that a device or implant has been replaced at no cost or with full credit; this will reduce the payment by the estimated device offset amount,
  • FC Modifier – represents devices replaced with partial credit; it reduces the payment by one-half of the device offset set for full credit,
  • TC Modifier – signifies that only a technical component, such as an X-ray, is being billed.

Claim submission

Claim submissions determine the amount of reimbursement a healthcare provider will receive after clearing the dues. They usually come in paper or electronic claims forms, which include:

  • Required documents
  • Verification
  • Evidence of the procedures

When dealing with claim submissions, you mustn’t report any services that are already included in the payment for covered surgical procedures. This can include HCPCS Level II codes, separate line items, or already mentioned procedures, drugs, supplies, and devices. 

Claim submissions should also offer a detailed insight into the procedures. Thus, they must be compiled by following the applicable standards. This includes:

  • Patient data
  • Diagnosis and procedure codes
  • Associated charges for the rendered services

By providing accurate claim submissions, you ensure timely and precise payment for your services.

Reimbursement procedures

Reimbursement is a process through which employers pay back the amount of money spent for business purposes by employees. Once the claim submission has been filed, the payor is tasked with assessing its accuracy. Depending on the results from the revision, they can either approve or deny the reimbursement request.

In this step of the ASC billing process, it’ll be determined if you’ll be receiving payment for the services you’ve offered. Remember that the reimbursement rates are lower than those of hospital or inpatient facilities. But you’ll still be able to cover most costs. The best way to ensure you receive an adequate reimbursement is to work with the payors and negotiate a favorable rate.

Reimbursement procedures
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Compliance Considerations for ASC Billing 

With the annual updates set in place, ASCs must always stay informed on the current healthcare regulations, especially when they affect the billing and coding. Understanding these changes is crucial for maximizing revenue, documenting claims, and avoiding penalties. If you want to ensure your regulatory compliance, follow the mandatory regulations below.

Mandatory regulations

Medicare certification

Always ensure your business has all the needed licensure. You’ll also need to meet the Conditions for Coverage for your reimbursement to be paid off. These regulations cover the medical staff qualifications, building layout, and day-to-day functioning. 

Medicare payment resources

The rates for the upcoming year are proposed in the summer and are finalized in the fall. They can be accessed through the Medicare website, containing all the needed information. It’s best to keep track of the changes to ensure ASC is paid appropriately.

Quality reporting

Medicare has a uniform quality reporting system. This allows ASCs to prove their quality measure performance. Furthermore, there’s an ASCQR Program to inform you about the latest required measures. Doing so will help you avoid payment reductions in the following year.

Emergency preparedness

ASCs must perform risk assessments. This includes developing policies and procedure plans and completing training for the final plan. 

What happens if you don’t follow regulatory compliances

Always remember that these facilities are highly regulated through federal regulations. Failing to oblige under the rules may lead to severe consequences and issues. 

First, you may face serious penalties if you don’t follow the regulatory changes. This is especially serious if it comes to enforcement actions. Such are fines, repayment demands, audits, and government program suspensions. Not only will these actions hurt you financially, but they may also ruin your reputation. Thus, you should update the proper billing practices to avoid further complications.

The best way to do so is through internal and external audits. They are an effective way of identifying any potential compliance gaps and ensuring a flawless workflow. The internal ones focus on assessing documentation accuracy, billing processes, and coding practices. External audits stick to objective assessments of compliance practices and ASC billing.


After discovering the ambulatory surgery center billing guidelines, you can easily see why this process is so important and delicate. Since it directly affects the reimbursement of your services, you must ensure it’s done correctly and without any mistakes. Since the coding and billing process is quite tricky and difficult, think about hiring a professional consultant to guide you through it. 

Doing so will ensure your ASC is working flawlessly and by following the necessary compliance regulations. You’ll avoid many setbacks and future issues if you have a helping hand to guide you from the beginning of the process. Lastly, if you ever feel lost during an ASC billing, you can always come back to this article and remind yourself of the essentials!

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