Complete Blood Count (CBC) with Differential
What it measures
A CBC measures red blood cells, white blood cells, platelets, hemoglobin, and hematocrit. The 'with Differential' part breaks down the white blood cells into their five types — useful for identifying infections, inflammation, and certain blood disorders.
When it’s ordered
Routine physicals, fatigue workups, suspected infections, monitoring chemotherapy, follow-up on prior abnormal results.
Medicare coverage
Governed by NCD 190.15 (Blood Counts). Medicare uses an inverted covered-codes list — most diagnoses are covered unless explicitly excluded. A general 'Z00.00' (routine exam) code often won't justify the test by itself; pair it with a specific symptom or condition.
Typical price
Medicare allowable runs around $7–11. Commercial cash prices range from $15 to $90 depending on the lab.
One thing to watch
Use the Code Lookup tool for the full list of accepted ICD-10 codes in your state.