Back in October, I looked into denial reports for a clinic in Paramus, NJ. Two clinicians, good patient flow, and experienced biller with five years of experience. What’s their denial rate? 22 percent! One in five claims was being denied. The owner didn’t have any clue about it since they never calculated denials as a percentage. All they saw were some denied claims coming in from time to time. That’s exactly why having a dedicated physical therapy billing service matters they track these numbers so you don’t miss them.
That’s not how it usually happens, and this issue doesn’t need to happen. Most of the claims that get denied in physical therapy can be prevented when you find what causes denials. By now, I’ve done auditing for numerous clinics, and there were always these ten issues appearing in each one. Below, you’ll find those ten mistakes in the descending order of frequency they cause denials. If you’re already overwhelmed, consider working with a physical therapy billing service that catches these issues before they cost you money.
1. Incomplete/Incorrect Information for the Patient
Misspelled surname. Incorrect date of birth. Insurance number misaligned by one number. Seems insignificant? It costs a bundle. Recently, I examined a set of 40 denial claims from a physician’s office in Clifton, and 17 of those cases were completely due to data entry errors. Yes, 17. And the solution couldn’t be any easier – confirm all of the patient’s demographics and insurance information at every visit, not just the first one.
2. Eligibility and Coverage Issues
Patient comes in for treatment, claims are sent, and payer responds by saying, “The patient was not eligible for coverage on the date of service.” This happens more than a few times a month in clinics where I work. The reason may be the lapse in patient’s coverage, change in insurance provider, or exclusion of PT services under patient’s unique benefit plan. Always check for patient’s eligibility. Don’t just check once a month. Do it prior to each visit. Automated tools do this within seconds.
3. Lack of Prior Authorization When it Should Have Been Secured
The use of prior authorization is spreading rapidly. There have been new rules put in place by CMS for 2026, and many private health insurance plans are joining in as well. In case your patient needs to secure a prior authorization first but you failed to do that before rendering care, their claim will be denied outright without any exception possible. You need to know which insurance companies require a prior authorization, how many visits they authorize, and how long the authorization lasts. It is one of the most costly mistakes in physical therapy billing since the treatment has already been provided.
4. Medical Necessity Not Proven in Documentation
The issue of medical necessity has become a focal point for Medicare in recent years. It is imperative that your therapist’s documentation makes clear that continued PT is necessary from a medical standpoint. “Improving patient” does not suffice; it is important to demonstrate documented functional impairments, goals, and a need for skilled therapy (and not just exercise). I advise therapists to document as if an auditor were reading the notes, because sooner or later there will be one.
5. Misapplication of the CPT Codes
Use of code 97110 for procedures that were actually 97530. Application of the 97140 code without any documentation to justify manual techniques. Submission of the code 97161 when the visit was actually a reevaluation coded as 97164. Coding mistakes lead to automatic denials; moreover, they are not only common but rather embarrassing. It is important to fix this problem using two approaches: proper training of therapists in using codes as well as billers in checking documentation.
6. Modifier Errors
Forget the GP modifier when you billed your Medicare PT claim? Denied. Failed to append KX after crossing the $2,480 therapy threshold for a PT or OT? Denied. Forgetting the CQ modifier if the PTA did more than 10% of the work? Denied. Modifier errors are responsible for a large number of preventable rejections in PT claims. At any time, there are over 15 different modifiers available for use, and your biller must know when and where they apply. Payors will not give you points for being close.
7. Unit Count Calculation Errors Under the 8-Minute Rule
I’ve written an entire blog just on this issue because of the headaches it causes! Billers calculate minutes individually per code, instead of adding all timed minutes first. Others may bill a unit of code with less than the 8 minute minimum amount of time provided. Yet others may include untimed codes in the total minutes used. Each error leads to improper unit counting, and hence, rejection of the claim. There was a clinic in Morris county that had been making this mistake for two months! It cost them approximately $9,200.
8. Duplicate Claims Submission
This is surprising to some extent, but it actually happens. The claim is submitted; the biller does not receive any acknowledgment of receipt after one week and then re-submits the claim; the payer considers them duplicate and rejects both. Another case scenario is when a practice management software glitch sends the same claim more than once on its own. The remedy here would be to log all claim submissions including their dates and to check the claim status with the payer before re-submitting anything.
9. Missing the Timely Filing Deadlines
All insurance companies have a deadline for claim filing; with Medicare you have one year and other commercial payers provide 90 up to 180 days period for filing claims. Once you miss that period, you can never recover the claim again. This is another very costly error; I have seen practices miss deadlines due to delays in correction of denials. The claims that were rejected due to errors during the original submission became revenue loss permanently.
10. Problems with Coordination of Benefits (COB)
If you have two insurance plans, then it’s imperative that both primary and secondary insurances should get billed properly. In case you bill your secondary insurance plan in the first place or you provide inaccurate information about your primary insurance plan, then both claims will get rejected. Such problems with COB are most frequently faced by patients who have a Medicare plan as well as some additional supplemental insurance plans. Another type of patients affected in this respect include those children who have two different parent insurance plans.
Stop Making Assumptions. Start Accumulating Money.
Every denial listed above is avoidable. It is not avoidable in theory; rather, it is practical, solvable right now. The reason is that fixing those issues requires paying close attention, knowing payer policies, and monitoring denials – all of which is not possible for small-to-midsize PT practices working with in-house billers.
That’s where a dedicated physical therapy billing company comes in. It is not about second-guessing any of your medical decisions. But, it does include ensuring that every penny you’ve rightfully earned ends up in your bank account.
It’s been designed by Park Medical Billing with that in mind. Their team identifies any modifier mistakes before sending out the claim. They monitor authorizations so that visits are not charged without authorization. They check eligibility prior to every visit. They process denied claims quickly, within only 7 to 14 business days, solving most claim denials fast. And their clients see an increase in revenues of at least 20% during the first 6 months because money was always there.
The reason Park stands out among a dozen other billing companies that you could call tomorrow is specialization. They specialize in physical therapy billing. They understand the 8-Minute Rule, they understand the modifier combinations in relation to Medicare and commercial payers, they know when CQ is relevant and when it isn’t, and they prepare individualized reports that will help you understand what happens with your money.
Started by Chol Park, located in Englewood, New Jersey, BBB A+ rating, helping physical therapy practice owners in NJ, NY and all around America. With more than ten years of experience in physical therapy billing and medical claims processing under their belt.
Do you have a high percentage of claim denials? You do? Then you should definitely check with Park about their free consultation. They will review your statistics, find the reasons for errors, and offer a detailed explanation of how your practice needs to change to improve your chances of success.
Written by the billing specialists at Park Medical Billing experts in RCM, ICD-10 coding, physical therapy billing, and revenue cycle optimization for USA-based healthcare practices.
Frequently Asked Questions
1. How much is an acceptable denial rate in physical therapy?
According to industry standards, the ideal denial rate is in the range of 5%-8%. If the rate goes beyond 10%, it implies that the practice is losing substantial amounts of income due to avoidable reasons. Physical therapy clinics usually operate at a higher rate than others due to the fact that physical therapy billing involves unique criteria such as timed codes, modifiers, and medical necessity that standard procedures ignore.
2. Is it possible to contest the denial of physical therapy claims?
Yes, it is. It is estimated that 40%-60% of appealed denials can be reversed. However, appeals must be filed within a certain timeframe, which is typically 30 to 90 days after receipt. One has to attach corrections or extra documentation. Those clinics that manage to recover the largest portion of lost incomes due to denials act on rejection immediately in the first week, not in several months.
3. Which payer tends to deny the most PT claims?
While Medicare is usually the toughest payer in terms of documentation and modifiers. But the commercial payers such as United Healthcare and Aetna have become much tougher with their denials in 2026. The answer will vary based on your specific payer mix – this is precisely the reason why your denial rate should be tracked separately for each payer.
4. How can a billing service help decrease my denial rate?
A dedicated physical therapy billing service catches errors in claims before submitting them, not afterward. They check the eligibility and requirements for authorization, code the CPTs and modifiers, and submit clean claims within 24-48 hours. In case any denials still occur, they handle them instantly using a denial management process. It’s not uncommon for clinics to have their denial rate cut to less than 7% in 90 days of working with a PT billing firm.
5. Which PT denial is the most costly for the client?
Denials associated with prior authorizations and those related to the expiration of timely filing dates. Both are virtually irretrievable denials. In the former case, the service has already been provided, and there is no chance of approval afterwards in most scenarios. In the latter case, the claim is forever gone from the system, even if the procedure was valid and correctly recorded.
