Your Payer Contract May Be Paying You Less Than You Think

A contract is signed once. It is rarely read again.

Most practices treat a payer contract as a fixed reference point: the rate was negotiated, it was filed, and it is assumed to still apply. But a contract signed five years ago describes a version of the practice that may no longer exist. What changed in the meantime is rarely a single event. It is a slow accumulation of small ones, and none of them individually triggers a review.

This is different from a single claim being paid wrong. A misapplied rate on one claim is an operational error. Contract leakage is what happens when the whole reimbursement structure has drifted away from what was actually negotiated, and nobody has gone back to check.

How a contract drifts, one change at a time

None of the following is unusual on its own. What makes them add up to leakage is that each one requires a separate, deliberate update to keep the contract’s terms current, and that update is easy to skip.

Fee schedules change on the payer’s side. Commercial contracts may be tied to a percentage of a published fee schedule, or to a proprietary schedule the payer maintains and updates. When the underlying schedule changes, the dollar amount your contract produces changes with it, even though the percentage or formula in the contract text has not moved. If nobody is tracking the schedule versions, the practice has no way to know whether the current payment reflects the current schedule.

The contract gets amended, and the amendment doesn’t fully propagate. Amendments typically address a specific issue: a new rate for a specific code, a carve-out for a high-cost service, a change to one clause. The amendment is signed, filed, and applied to the one thing it addresses. Whether it is reflected everywhere it should be, including in the payer’s own claims-adjudication system, is a separate question that the signing process does not answer.

New CPT codes are released annually, while HCPCS Level II codes are updated on a more frequent cycle, and existing codes are revised or retired. A contract written before a code existed may not specify how that code should be paid, particularly if the agreement does not contain a methodology for newly introduced services. Where no such methodology exists, new codes may be paid according to a default rate or process in the payer’s system, which may or may not reflect what the contract would produce if the code had been explicitly addressed.

Reimbursement for specific services changes independently of the fee schedule. Payers periodically revise medical policy, prior authorization requirements, and payment rules for individual service categories. A service that was reimbursed one way when the contract was signed can be paid differently now, through mechanisms that never touch the base contract language.

The practice itself changes. A new location, a new group NPI, a provider joining or leaving, a change in how a service is billed (incident-to versus independently, for example) can each affect which fee schedule, which network, or which rate applies. If the payer’s records were not updated to match, claims may be processing against the wrong version of the practice.

The billing system was never fully configured to reflect the contract. Many practice management systems store a single global fee schedule rather than payer-specific, plan-specific contracted rates. When that is the case, the system cannot flag a short payment, because it never had the correct expected amount to compare against. The contract exists as a document. It does not exist as a working rule inside the software that processes the money.

Any one of these is a small, ordinary event. A payer updates a schedule. A code gets added. A provider changes status. None of them are billing errors in the way a wrong modifier or a missed authorization is an error. But each one moves the actual reimbursement further from the number in the original agreement, and there is no automatic mechanism that keeps them in sync.

The assumption that nothing has changed

The practice believes it is being paid “the contracted rate.” That belief is usually based on the fact that claims are being paid, payments are posting, and nothing looks obviously wrong. It is rarely based on an actual comparison between current payments and the contract’s current terms, because that comparison requires two things most practices don’t have readily available: a contract that has been updated to reflect every amendment and rate change, and a billing system that stores those terms in a form that can be checked against every remittance.

Without both, “we’re getting the contracted rate” is an assumption, not a finding.

Why this doesn’t surface on its own

Denial management is primarily designed to find claims that were rejected. Payment posting is primarily designed to record what came back. Neither process, by itself, is designed to determine whether a paid claim reflects the current, fully amended version of the contract, because that question requires a reference point neither process maintains: an up-to-date, code-level, plan-level table of what the contract requires today, not what it required when it was signed.

Contract terms also tend to live in one place, as a PDF or a scanned document, while billing operates in another, the practice management system. Nobody owns the job of keeping them aligned, because it doesn’t map cleanly onto either the billing role or the front-office role. It sits in between, and work that sits in between departments tends not to get done.

What a contract and reimbursement review actually checks

The exercise is different from a claim-level payment audit, though the two connect. A contract review asks a prior question: is the reimbursement structure we operate under today still the one we actually negotiated? In practice that means:

• Reconstructing the current, fully amended version of each payer contract, with every rate change and carve-out incorporated, not just the original signed document
• Confirming which fee schedule version and which effective dates apply to each code today
• Checking that newer codes relevant to the practice have an assigned rate consistent with the contract’s methodology, where one exists, rather than a payer default
• Verifying that practice changes, such as a new location or a change in provider status, are reflected in how the payer classifies the practice
• Testing whether the billing system’s stored expected rates match what the current contract actually requires

The output is not a list of denied claims. It is a corrected, current picture of what the practice should be getting paid, which then becomes the baseline every future claim can be checked against.

Where this leads

A contract that has drifted from what it should say is not something a single audit fixes permanently. Fee schedules will update again. Codes will change again. The practice will keep evolving. The value of doing this work once is that it resets the baseline; the value of doing it on a schedule is that the baseline stays current.

WCH Service Bureau supports medical practices with this type of contract and reimbursement review, helping compare payer terms with actual reimbursement and identify gaps that can affect revenue over time.

If it has been a while since your contracts were checked against how they are actually being paid, that comparison is a practical place to start.

Sources

1. American Medical Association, “AMA releases CPT 2025 code set” — CPT Editorial Panel process, annual update cycle effective January 1. https://www.ama-assn.org/press-center/ama-press-releases/ama-releases-cpt-2025-code-set
2. American Medical Association, “CPT code set keeps pace with health care technology innovation” (420 updates in the 2025 release: 270 new codes, 112 deletions, 38 revisions). https://www.ama-assn.org/practice-management/cpt/cpt-code-set-keeps-pace-health-care-technology-innovation
3. CMS, HCPCS Quarterly Update — confirms the HCPCS Level II code set is updated on a quarterly cycle. https://www.cms.gov/medicare/coding-billing/healthcare-common-procedure-system/quarterly-update
4. MGMA Stat, “Regular auditing of payer payments crucial to ensure accurate reimbursement,” February 12, 2025. https://www.mgma.com/mgma-stat/regular-auditing-of-payer-payments-crucial-to-ensure-accurate-reimbursement
5. MGMA, “Analyzing Payer Contracts Playbook” — recommends collecting executed agreements, amendments/addenda and current fee schedules, mapping reimbursement rates for key CPT codes, and periodically reviewing EOBs for reduced reimbursement. https://www.mgma.com/playbooks/payer-contract-analysis
6. Becker’s Hospital Review, “WCH Service Bureau unveils Second Opinion RCM offering” — background on WCH’s existing billing-audit service line. https://beckershospitalreview.com/finance/wch-service-bureau-unveils-second-opinion-rcm-offering.html