CO-174 denial code
Service was not prescribed prior to delivery
How to fix it
Verify the order date. A retroactive order will not usually cure this.
How to prevent it
Ensure orders are dated and signed before delivery, not reconstructed afterwards.
The CO prefix marks this a contractual obligation. The balance is absorbed by the provider under the payer agreement and cannot be transferred to the patient.
In practice
A laboratory performs a test on a verbal request and obtains the written order two days later. The order carries the date it was signed, and the claim returns CO-174.
The order postdates the service on its face. Because orders are meant to authorise care rather than record it, an order dated after delivery does not establish that the service was ordered at all.
Verbal orders are usually acceptable where the practice documents them at the time and obtains written confirmation afterwards, but the contemporaneous documentation is what makes that work. Without it, the written order is all the reviewer sees.
What sits behind it
This is one of the harder denials to cure because the defect is on the face of the document. Unlike a missing signature, which can be supplied, a date showing the order came second cannot be changed without falsifying the record.
The workable practice is documenting verbal orders when they are received, with the date, time, ordering practitioner and content, and then obtaining written confirmation. The contemporaneous note is the evidence; the later signature confirms it.
Standing orders and protocols serve a related function for recurring services and are accepted by many payers where properly established. They have to be signed, dated, specific about which patients and conditions they cover, and reviewed periodically to remain valid.
Related codes
Terms used here — Medical Necessity · Denial · Appeal
How we handle it — Denial Management · Claims Management · Medical Billing & Coding
Primary sources
The rules behind CO-174, at the bodies that publish them.
- Evaluation and Management services guide (opens in a new tab)
Centers for Medicare & Medicaid Services — How E/M level is determined under the current medical decision making and time rules. The reference for any dispute about whether documentation supports a level.
- Medicare Claims Processing Manual (opens in a new tab)
Centers for Medicare & Medicaid Services — The operative manual for how Medicare claims must be coded, submitted, adjusted and appealed. When a payer policy and a vendor's advice disagree, this settles it.
- Medicare claims appeals process (opens in a new tab)
Centers for Medicare & Medicaid Services — The five levels of appeal, what each requires and the deadline for each. Missing a level's deadline ends the appeal regardless of the claim's merits.
Looking for a different code? Search all 190 CARC and RARC codes
Questions about CO-174
Usually, where they are documented contemporaneously with the date, time, ordering practitioner and content, and written confirmation follows. The contemporaneous note is what makes the later signature meaningful; without it the written order is the only evidence and it postdates the service.
Not without falsifying the record. Unlike a missing signature, which can genuinely be supplied afterwards, a date establishing that the order came second is a fact. The available argument is contemporaneous evidence that the order was actually given earlier.
For recurring services, considerably. Many payers accept them where they are signed, dated, specific about the patients and conditions covered, and reviewed periodically. A vague or stale standing order is treated as no order, so maintenance matters.
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