CO-286: Appeal time limits not met

What causes CO-286?

• The appeal window was counted from the wrong date — it usually runs from the remittance date, not the date of service
• The denial sat in a work queue while the window ran out
• A first-level appeal was filed in time but the second level was not
• The payer’s window for that plan is shorter than the one the biller assumed

How do you fix a CO-286 denial?

1. Check the plan’s actual appeal window and what date it runs from before conceding — they differ by payer and by product
2. Where there is good cause provision, file with the evidence of it; some payers accept documented submission attempts
3. Where the deadline is genuinely missed, this money is gone and the useful work is stopping the next one
4. Do not resubmit as a new claim to restart a clock — that is a timely filing problem, not an appeal, and payers detect it

Can CO-286 be prevented?

Every denial needs a date stamp and a deadline the day it lands, and the queue has to be worked oldest first. A denial nobody touched for 90 days is a decision to write it off, made by accident.

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-286 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.

• CO-45 — Charge exceeds the fee schedule
• OA-23 — Prior payer already adjudicated
• 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.