CARC 66: Blood Deductible

What it means

This claim line was reduced or denied because a blood deductible applies. Many health plans, including Medicare, require patients to either replace a certain number of units of whole blood or packed red cells each benefit period or pay for them out of pocket. The amount shown as adjusted is the portion tied to that blood deductible obligation, not a standard coinsurance or copay.

Common causes

Patient has not met or replaced the required blood unit deductible for the benefit period
Blood or blood product units billed were not identified as replaced by the patient or a blood bank
Incorrect revenue or HCPCS coding for blood products that triggers automatic deductible logic
First blood-related claim of the benefit period, so the deductible has not yet been satisfied
Blood administration charges billed separately without proper linkage to the blood product charge

How to fix it

Review the remittance advice to confirm how many blood units were subject to the deductible
Check the patient's benefit period history to see if blood units were already replaced or previously billed
Verify revenue codes (e.g., 038X) and HCPCS/CPT codes used for blood products are accurate and complete
If the patient or a replacement donor furnished blood units, submit documentation showing replacement to have the deductible waived
Bill the patient for the blood deductible portion if no replacement occurred and the adjustment is correct per payer policy
Contact the payer if the number of units subject to deductible appears incorrect based on your records

Appeal / resubmit

If you have documentation that the patient or a donor replaced the required blood units, submit it with a corrected claim or appeal referencing the specific units and dates. Include the blood bank's replacement certificate or similar proof if available. If the deductible was applied to units already satisfied in a prior claim within the same benefit period, provide the prior remittance advice showing those units were already counted. This information is educational and not a substitute for payer-specific appeal instructions.

Related codes

Frequently asked

What is a blood deductible?

It's a requirement under many plans, including Medicare Part A and Part B, that a patient replace a set number of blood units per benefit period or pay for those units themselves before the plan covers the rest.

Can the blood deductible be waived?

Yes, if the patient or someone on their behalf replaces the required blood units, the deductible can often be waived. Documentation of replacement is typically needed.

Is the blood deductible the same as the annual Part B deductible?

No, it's a separate requirement specific to blood products and is tracked independently from standard annual deductibles.

Who is responsible for paying the blood deductible if it's not waived?

Generally the patient is responsible unless replacement units are provided or another payer source applies.

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This content is for general informational purposes only and does not constitute billing or legal advice. Verify all denial handling with the specific payer's policies and guidelines.