Question: Our clinician admitted a patient in September and didn’t discharge her until October. Because of the ICD-10 implementation, we are not sure how to bill this claim. Do we use both ICD-9 and ICD-10 codes on the same claim since the dates of service span the implementation date?

Missouri Subscriber

Answer: No. You will need to submit two claims — one using ICD-9 codes and one using ICD-10 codes.

Here’s why: A claim containing both ICD-9 and ICD-10 diagnostic codes, regardless of the dates of service, will be returned on the basis that it cannot be processed, and you will receive no reimbursement for it.

Services that span from pre-Oct. 1, 2015, through and after that date must be split into separate claims. For instance, any outpatient or hospital services that span the implementation date will be billed as two claims — the first will be listed with the dates of service through Sept. 30, 2015, (using ICD-9 codes) and the second will be listed with dates of service Oct. 1, 2015, and later (using ICD-10 codes).

“A claim cannot contain both ICD-9 codes and ICD-10 codes. Medicare will RTP [return to provider] all claims that are billed with both ICD-9 and ICD-10 diagnosis codes on the same claim. For dates of service prior to October 1, 2015, submit claims with the appropriate ICD-9 diagnosis code. For dates of service on or after October 1, 2015, submit with the appropriate ICD-10 diagnosis code,” according to MLN Matters article SE1408.