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CO-110 Denial Code: Billing Date Before Service Date

CO-110 means the billing date predates the service date. The claim was submitted before the service it reports was provided, usually because of a future date of service, a date typo, or a claim released too early.

Code: CO-110 (CARC 110)
Status: Active In use since January 1, 1995.
Code set: Claim Adjustment Reason Codes (CARC)
Group codes: CO (Contractual Obligation): The provider must correct the claim. The amount is not billable to the patient.
Official description: Billing date predates service date.
X12 Claim Adjustment Reason Codes, retrieved September 25, 2026
Last verified: September 24, 2026 against the official X12 list.

What CO-110 means

CARC 110 reads billing date predates service date. The payer compared the date your claim was created or received with the dates of service on the claim, and at least one service date is later than the billing date. Payers do not pay for services that have not happened yet, so the claim or line is denied.

This is almost always a clerical or workflow error. The fix is usually quick: correct the dates or wait until the service is performed, then submit again.

Example: a visit on March 3 is keyed as May 3. The claim is sent on March 10. The payer sees a service date two months in the future and returns CO-110.

Common causes

A typo in the date of service in box 24A, often the month or year.
A spanning date range (from/to) where the end date is later than the submission date.
Recurring services, such as therapy or DME rentals, billed for a full month before the month ends.
Charges created from scheduled appointments instead of completed ones.
A wrong system date on the computer or billing software that generated the claim.

How to fix it

Compare each date of service in box 24A (and statement period dates on institutional claims) with the medical record.
If a date was mistyped, send a corrected claim. If the payer rejected it at the front end, fix it and send it as a new claim; if it was adjudicated, use resubmission code 7 in box 22 with the original claim number.
If services have not all occurred yet, remove the future dates and bill them after they happen.
Check the rest of the claim for other date issues before resubmitting, so it does not come back again.
No appeal is needed. CO-110 is corrected, not disputed.

How to prevent it

Block claim creation for appointments that are not checked out or completed.
Add a scrubber rule rejecting any date of service later than today. A Claims Validator catches this before submission.
Bill recurring monthly services only after the last date in the period.
Confirm workstation and server dates are correct.
For the difference between front-end rejections and payer denials, see claim rejection vs. denial.

Specialty notes

DME rental and PT/OT practices that bill a span of dates are most exposed. Set the “to” date to the last completed service, not the end of the authorization or rental period.

CO-16 (Claim/service lacks information or has submission/billing error(s).): Missing or invalid claim information, the general code some payers use for date errors.
CO-101 (Predetermination: anticipated payment upon completion of services or claim adjudication.): Predetermination, where future services are estimated rather than billed.
CO-14 (The date of birth follows the date of service.): Date of birth follows the date of service, a different date logic error.
CO-13 (The date of death precedes the date of service.): Date of death precedes the date of service.

CO-110 FAQ

How can a claim be billed before the service date?

Usually through a keying error, such as the wrong year or month, or when a claim with a future appointment date is released early. Some systems also create claims when services are scheduled rather than performed.

Is CO-110 a rejection or a denial?

Many payers and clearinghouses catch future dates as a front-end rejection. If it reaches adjudication and comes back as CO-110, fix the dates and resubmit as instructed by the payer.

Can I bill for a series of services before the last visit?

Only for dates that have already happened. Every date in box 24A must be on or before the date you submit the claim.

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