CO · Contractual ObligationCARC 242

Denial Code CO-242

Q: What does CO-242 mean?

CO-242 is a Contractual Obligation (CO) denial: "Services not provided by network/primary care providers." The plan says the services weren't provided by an in-network (or the required primary-care) provider. Under the CO group code the difference is treated as a provider/contractual responsibility rather than a patient balance.

Q: Is CO-242 the patient's responsibility or a provider write-off?

CO-242 carries the CO group code (Contractual Obligation): Provider/contractual responsibility — not billable to the patient while denied. A CO adjustment is the provider's responsibility, not the patient's: balance-billing the patient for a CO amount is a contract (and often compliance) violation. But CO does not automatically mean “write it off.” When the cause is fixable — missing information (CO-16), a modifier problem (CO-4), or NCCI bundling (CO-97) — you correct and resubmit, or appeal with documentation. You only truly write the amount off when it is a final contractual adjustment, such as the fee-schedule difference on CO-45.

Services not provided by network/primary care providers.

Source: X12 Claim Adjustment Reason Codes (CARC) & Group Codes. Maintained by the D3rx Clinical Billing Team.

What CO-242 means

The plan says the services weren't provided by an in-network (or the required primary-care) provider. Under the CO group code the difference is treated as a provider/contractual responsibility rather than a patient balance.

Why CO-242 happens

The rendering provider was out-of-network for the patient's plan
A plan requiring care from (or coordination by) a primary-care provider wasn't followed
A network or panel restriction on who may render the service
A provider not yet loaded as in-network on the date of service

What to do when you get CO-242

1Verify the rendering provider's network status with the plan for the date of service
2If the provider IS in-network but loaded incorrectly, correct the data and resubmit
3If a primary-care coordination/referral rule applies, confirm whether it was met or can be obtained retroactively
4If the provider is genuinely out-of-network under a CO arrangement, the difference is a contractual/provider responsibility

Got this denial right now?

Ask D3 whether to appeal or correct CO-242

Ask D3 about CO-242 Ask D3 about CO-242

CO-242 can go either way depending on the claim. Ask D3 tells you whether to appeal, correct, or just confirm status — free.

CO group code: who absorbs the charge

Contractual Obligation — Provider/contractual responsibility — not billable to the patient while denied.

A CO adjustment is the provider's responsibility, not the patient's: balance-billing the patient for a CO amount is a contract (and often compliance) violation. But CO does not automatically mean “write it off.” When the cause is fixable — missing information (CO-16), a modifier problem (CO-4), or NCCI bundling (CO-97) — you correct and resubmit, or appeal with documentation. You only truly write the amount off when it is a final contractual adjustment, such as the fee-schedule difference on CO-45.

Appeal, correct, or write off CO-242?

Start by confirming network status: if the provider was in-network but mis-loaded by the plan, that's a correction/appeal with the contract or directory listing. If a PCP coordination/referral requirement was missed, pursue a retroactive referral where the plan allows. Under the CO group code you cannot bill the patient (contrast PR-242, where the balance is the patient's); the patient-vs-provider liability turns on the group code.

Timing & deadlines

Appeal or correct within the payer's window (commercial ~180 days from the remittance; Medicare-related plans 120 days for redetermination); corrected claims follow timely-filing limits (~90-180 days commercial; Medicare 12 months from date of service).

Example

A patient sees a provider the plan lists as out-of-network, and the claim returns CO-242. If the provider was actually contracted on that date but loaded incorrectly, the network/directory record supports an appeal; if truly out-of-network under a CO arrangement, the difference is a provider/contractual write-off.

Prevent CO-242 going forward

Verify provider network status with each plan before scheduling
Confirm PCP coordination/referral requirements at registration
Keep network participation/effective dates current per payer
Flag plans with narrow networks or strict gatekeeping

Code families most affected

Out-of-network and narrow-network claims
Gatekeeper/PCP-coordination plans
Panel-restricted services

Related codes

Denial codes you'll often see alongside CO-242

PR-242 CO-95

Payer notes

CO-242 and PR-242 share CARC 242 ('services not provided by network/primary care providers') — the group code decides who absorbs it. CO-242 is provider/contractual; PR-242 shifts the balance to the patient (e.g., a knowing out-of-network choice).

Not sure how to work CO-242?

Ask D3 whether CO-242 should be appealed, corrected, or simply confirmed — free, backed by CMS, Medicare, and major-payer data.

Ask D3 about CO-242 Ask D3 about CO-242 All denial codes

Medical billing disclaimer

CARC/RARC definitions are the standardized X12 set; group-code semantics follow the X12 Claim Adjustment Group Code standard. Filing and appeal windows vary by payer — the standard anchors shown (Medicare redetermination 120 days from the remittance; Medicare timely filing 12 months from date of service; most commercial payers ~90-180 days) are general references, not a guarantee for any specific plan. Always confirm the rule in the payer's provider manual before acting. D3rx is not responsible for claim outcomes.