CO-45: Charge exceeds the fee schedule

What causes CO-45?

• Normal contractual adjustment, correct and expected
• The payer loaded the wrong fee schedule for your contract
• The claim was priced as out of network when you are in network
• A contract escalation was agreed and never applied on the payer side

How do you fix a CO-45 denial?

1. Compare the allowed amount against your contracted rate for that CPT. If they agree, post the adjustment and move on
2. If the allowed amount is short, this is a payer configuration error and it is affecting every claim for that code, not just this one
3. Escalate underpayments as a batch with a spreadsheet of examples rather than one call per claim
4. Recalculate after every contract renewal, because this is when loaded rates most often go stale

Can CO-45 be prevented?

Most practices post CO-45 automatically and never check it. Systematic underpayment hides here precisely because the code looks routine.

A denial like this one is the recurring cost that medical billing outsourcing is built to take off your desk — a dedicated seat working the queue instead of it waiting for whoever has a free hour.

Codes worked the same way

CO-45 is checked against the contract before any work is done. So are these, which is why a queue sorted by recovery route moves faster than one sorted by code number — the same person, in the same system, with the same evidence to hand, clears all of them in one pass.

• OA-23 — Prior payer already adjudicated
• CO-286 — Appeal filed too late
• CO-253 — Sequestration reduction
• CO-256 — Not payable under the contract
• CO-B10 — Component already paid
• N381 — Per contract

Specialties that name this among their costliest

These are specialties whose own worst denials include one of this kind. The line under each is the denial they name, quoted from their page so you can see what the link is based on.

• Anesthesia
  Post-op pain blocks bundled into the anesthesia claim
• Ophthalmology
  Retinal imaging and fundus photography done at the same visit, with one line denied as bundled because the record never gives a separate reason for each test.
• Otolaryngology
  The operative note does not state which sinuses were entered on which side, so the sinus surgery lines are bundled together or only one side is allowed.
• Urgent Care
  A global urgent care case rate billed alongside a separate evaluation and management line where the contract pays one or the other, and the second line drops off
• Primary Care
  A preventive visit and a same-day problem visit written up in one undivided note, so the problem visit bundles into the wellness visit and is not paid separately.
• Oncology
  Payer required the drug through its contracted specialty pharmacy, the practice infused from its own stock, and the buy-and-bill claim was denied in full.

What leaving it costs

Working a denied claim costs $57.23 per denied claim in administrative time (source) — before any of it is recovered, and whether or not it ever is.

Payers ultimately pay roughly 90% of claims even while using an initial denial to slow payment (source), so the reason one sits is rarely that nobody knows how to work it. Put your own denial count in.

Questions

Code descriptions are the standard X12 claim adjustment reason and remittance advice remark code text. Payer policies differ, and the payer’s own coverage policy governs any individual claim. This page is working guidance, not legal or clinical advice.