Every denied claim adds days to your accounts receivable as your team works to resolve issues, resubmit documentation, and chase payments. Those delays compound across hundreds of claims, pushing your A/R days higher. High-performing practices maintain A/R days at 30 or below, while average practices struggle at 40-50 days.
If you’re above 50, specific mistakes are creating a backlog of denials that keep cash tied up instead of funding your operations. The real issue isn’t that your team lacks effort or skill. It’s those specific preventable mistakes that keep triggering denials that tie up your cash for weeks or months. Here are the 10 most common mistakes that cause denials and how to fix them.
Tired of chasing denied claims and watching A/R days climb?
Mistake #1: Verifying Insurance Only Once at Scheduling
Your front desk checks insurance at scheduling, then nothing gets verified again until the claim is denied for “patient not covered.”
The A/R impact
Eligibility issues cause over 60% of all denials. Insurance status may change constantly between scheduling and service dates. Each eligibility denial adds 15-30 days to your A/R while you work with patients to determine who should pay.
How to Fix It?
Verify twice, at scheduling and 24-48 hours before the appointment. Automated eligibility tools can flag coverage changes immediately. Practices using real-time verification report 30-40% collection improvements.
Mistake #2: Missing Prior Authorization Deadlines
Authorization requests sit for days before submission or lack complete documentation, burning through approval windows.
The A/R impact
Prior authorization denials hit 9% of all claims, but target your highest-value procedures. In 2023, insurers denied 3.2 million prior authorization requests, though 82% of appeals overturned these denials. Missing the deadline turns a $5,000 collectible claim into a write-off, after you’ve already provided the service.
How to Fix It?
Create a tracking system with automated deadline alerts. Build payer-specific checklists for each procedure type. Assign one authorization coordinator. Set internal deadlines 3-5 days ahead of payer deadlines for buffer time.
Mistake #3: Using Outdated or Non-Specific Diagnosis Codes
Your team uses the same ICD-10 codes they’ve always used, unaware of annual updates, or consistently bills unspecified codes when the record documents specific details.
The A/R impact
ICD-10 updates every October 1st. The 2025 update included 252 new codes, 36 deletions, and 13 revisions. Using deleted codes triggers automatic denials. Lack of specificity causes rejection even when codes are valid. Each coding denial requires manual review and resubmission, adding weeks to collection timelines.
How to Fix It?
Run quarterly coding audits on high-volume services. Subscribe to coding update alerts. Create quick-reference guides showing the most specific codes. Train staff that unspecified codes are last resorts, not defaults. Set up claim scrubbers that flag unspecified codes before submission.
Mistake #4: Submitting Claims Without Medical Necessity Documentation
Clinical notes explain what was done, but fail to articulate why it was medically necessary according to payer guidelines.
The A/R impact
Medical necessity denials represent only 6% of total denials, but hit your highest-value claims. They take the most time to appeal. A $3,000 procedure denial might require 5-10 hours of staff time gathering records and writing appeals. That revenue sits aging for weeks or months.
How to Fix It?
Create documentation templates prompting providers to include medical necessity language. For high-value procedures, implement pre-submission reviews where billing specialists verify documentation supports services billed. Build a library of successful appeal letters organized by procedure and payer.
Mistake #5: Failing to Track Coordination of Benefits
When patients have multiple coverages, your team guesses at the billing order or bills whoever the patient mentions first.
The A/R impact
COB errors create denials from both insurers, each saying the other should be primary. Claims bounce between insurers with neither taking responsibility, adding 30-60 days to your A/R. COB issues contribute to t8% of denials caused by administrative errors.
How to Fix It?
Always ask about secondary coverage during registration. Use the clearinghouse COB tools to verify the billing order before submitting. Contact both payers directly when uncertain and document their guidance. As of January 2025, many payers require proof of timely primary submission with secondary claims.
Mistake #6: Ignoring Timely Filing Deadlines
Claims sit awaiting documentation signatures. Denied claims aren’t resubmitted quickly. The payer’s filing deadline passes.
The A/R impact
Timely filing violations account for 4-7% of denials and are almost never recoverable. These convert collectible revenue directly to write-offs. Deadlines vary dramatically: Medicare allows 365 days, but commercial payers range from 30 to 180 days. A practice submitting 500 claims monthly could lose over $50,000 annually from just 5% missing deadlines.
How to Fix It?
Create a dashboard showing every payer’s deadline visible to your billing team. Implement automated workflows pushing claims out within 48-72 hours of completed documentation. Set alerts at 60% of the allowed time, not three days before the deadline. For denials, implement a 7-day rule: every denial logged and action initiated within 7 days of receipt.
Mistake #7: Entering Incorrect Patient Demographics
Patient names are misspelled, dates of birth transposed, policy numbers contain typos, or subscriber relationships are wrong.
The A/R impact
Administrative and data entry errors cause 18% of denials. Each demographic mismatch requires 20-30 minutes to contact patients, verify information, correct claims, and resubmit. Twenty claims per week means significant added time to your A/R cycle.
How to Fix It?
Invest in insurance card scanning technology that auto-populates information, eliminating manual entry. Implement tablet check-in where patients verify demographics before every visit. Train front desk that accuracy beats speed, 30 extra seconds prevents 20 minutes of rework.
Mistake #8: Using Generic Appeal Letters for All Denials
Your team uses the same appeal template for every payer and situation, changing minimal details but keeping the basic structure identical.
The A/R impact
Each payer has specific appeal requirements and documentation expectations. Medicare wants appeals structured completely differently from UnitedHealthcare. Generic letters get denied at higher rates, waste limited appeal opportunities, and extend the unpaid claim time. Providers successfully overturn 54% of denials when properly appealed; generic strategies leave money on the table.
How to Fix It?
Build a library of payer-specific appeal templates based on successful appeals. Track overturn rates by payer and denial reason. When you win an appeal, save that letter as a template. Include specific regulatory references and medical literature when appropriate. Respond quickly; many payers have 30-60 day windows.
Mistake #9: Not Analyzing Denial Patterns
Your team works on denials individually but doesn’t track patterns. The same denials from the same payers for the same reasons keep recurring.
The A/R impact
Without pattern analysis, you can’t fix root causes. The same mistakes generate denials month after month, each adding days to A/R. According to industry data, 90% of denials are preventable once you identify and address root causes.
How to Fix It?
Implement denial tracking, capturing reason codes, payer, service type, provider, and resolution outcome. Review monthly to identify patterns. When the same denial repeats, stop and fix the process creating it. Share successful strategies across your team so everyone benefits.
Mistake #10: Working All Denials the Same Way
Your team works the denial queue chronologically. A $200 claim gets the same attention as a $5,000 claim because “we work them in order.”
The A/R impact
Working a $150 claim for two hours makes no financial sense, while a $4,500 claim sitting untouched for three weeks directly damages revenue. One hundred claims averaging $300 versus 10 claims averaging $3,000, spending a week on the former while $30,000 ages is financially backwards.
How to Fix It?
Implement value-based prioritization. High-value denials over $2,000 get immediate attention from experienced staff regardless of age. Create aging thresholds where denials at 30 days get escalated action. Assign denial types to specialists: one handles eligibility, another coding, and a third authorizations.
The Connection to A/R Days
These mistakes create direct paths to elevated A/R days. Eligibility denials mean claims bounce back weeks after submission. Prior authorization denials mean fighting for payment on already-delivered care. Coding errors add 15-30 days for correction and resubmission. Missing documentation triggers 45-60 day appeal processes. Timely filing violations convert receivables to write-offs. Administrative errors create multiple-bounce rework loops.
When these compounds are across hundreds of monthly claims, they create a persistent backlog, keeping A/R days elevated. High-performing practices with A/R under 30 haven’t eliminated denials; they’ve built systems preventing most before submission and resolving unavoidable ones within 7-10 days.
Want billing services that keep A/R under 30 days consistently?
Ending Note
Choose your biggest pain point and address it this month. If eligibility denials are the majority, implement two-step verification as soon as possible. On the other hand, if timely filing is the issue, create a deadline spreadsheet and set calendar reminders. It all depends on your practice.
Pick one, implement fully, measure results, then move to the next. Practices taking this focused approach see measurable A/R improvements within 60-90 days. Your A/R days are a scoreboard showing how well your denial prevention systems work.
