A “clean claim” is a claim that’s accepted by a payer on the first submission, with no errors, no missing information, and no need for additional documentation before it can be processed for payment. It sounds simple, but the clean claim rate is one of the single best indicators of how well a practice’s billing operation is actually running.

For a claim to qualify as clean, several things have to line up at once: the patient’s eligibility and coverage details have to be current, the diagnosis and procedure codes have to be accurate and properly linked, any required prior authorization has to already be on file, and the claim format itself has to meet the specific payer’s submission requirements.

The reason clean claim rate matters more than almost any other single metric is that it’s a leading indicator — a low clean claim rate today predicts denials, rework, and delayed cash flow in the weeks ahead. Practices typically aim for a clean claim rate in the mid-to-high 90% range; anything meaningfully below that is usually a sign of an upstream problem — often eligibility verification or coding accuracy — worth investigating before it compounds further.

An Explanation of Benefits (EOB) is the document a payer sends after processing a claim, showing exactly how they arrived at the payment amount — or the denial. Reading one correctly is a basic but essential skill for anyone working claims follow-up.

The key fields to look at, in order: the billed amount (what was originally charged), the allowed amount (what the payer’s contract actually permits for that service), any adjustment or write-off amount (the difference between billed and allowed, which the practice cannot collect from the patient), the amount the payer actually paid, and the patient responsibility (copay, coinsurance, or deductible still owed).

The field that causes the most confusion is the reason code or remark code section — a short alphanumeric code explaining any reduction or denial. These codes are standardized across payers (CARC and RARC codes), which means once staff learn to recognize the common ones for their specialty, EOBs become far faster to process. Keeping a simple internal reference sheet of the reason codes that show up most often — and what action each one requires — saves significant time compared to looking each one up individually.

Prior authorization is a payer’s requirement that certain services, procedures, or medications be approved before they’re performed, not after. Skipping this step doesn’t just risk a delay — for many payers, it results in an automatic denial with no option to appeal after the fact, regardless of medical necessity.

The services that typically require prior auth vary by payer and plan, but commonly include advanced imaging (MRI, CT scans), certain surgical procedures, specialty medications, and some outpatient procedures. The specifics change often enough that relying on memory or last year’s rules is a common source of denials — checking current requirements per payer, per service, is the only reliable approach.

The practices that avoid prior authorization denials build it into their scheduling workflow rather than treating it as a billing-department task after the fact. When prior auth status is checked at the time a procedure is scheduled — not the day before, and not after the visit — there’s enough lead time to actually secure approval before the date arrives, rather than discovering the requirement only when the claim bounces back.

Telehealth visits are billed differently from in-person visits in several specific ways, and getting these details wrong is a common source of denials for practices that added virtual care without adjusting their billing workflow to match.

The two elements that matter most are the place-of-service code and the modifier. Depending on the payer, a telehealth visit might require place-of-service code 02 (telehealth, patient not in their home) or 10 (telehealth, patient in their home), plus a modifier such as 95 or GT indicating the service was delivered via real-time audio-video technology. Using the wrong combination — or omitting the modifier entirely — is one of the most frequent telehealth-specific denial causes.

Payer rules for telehealth also vary more than for in-person care, particularly around which CPT codes are eligible for telehealth delivery at all, and whether audio-only visits (without video) are reimbursed the same as audio-video ones. Because these rules have shifted repeatedly across payers in recent years, practices offering telehealth benefit from maintaining a simple, regularly updated reference of which codes and modifiers each major payer currently accepts, rather than assuming last year’s rules still apply.

Modifier 25 indicates that a significant, separately identifiable evaluation and management (E/M) service was performed on the same day as another procedure by the same provider. It’s what allows a practice to bill for both the office visit and the procedure performed during that same visit, rather than having the E/M service bundled into the procedure’s reimbursement.

The key word payers scrutinize is “separately identifiable.” The E/M service has to represent genuinely distinct work from the procedure itself — not just the routine evaluation that leads into a planned procedure. Documentation needs to clearly support that the provider performed and documented a distinct evaluation, with its own history, exam, and medical decision-making, beyond what the procedure itself required.

Modifier 25 is also one of the more frequently audited modifiers, precisely because it’s sometimes applied too liberally. The practices that use it correctly and confidently are the ones with clear documentation habits — providers who note the distinct reason for the E/M component clearly, rather than relying on the modifier alone to justify the claim. When documentation genuinely supports it, modifier 25 is legitimate and important reimbursement; when it doesn’t, it’s one of the more common triggers for a payer audit.