CMS Pub. 100-04, ch. 17, § 20.1

In general, CMS establishes a single, national payment limit for A/B MAC (A), A/B MAC (B), A/B

MAC (HHH) and DME MAC payment for each Medicare-covered drug whose payment is determined

based on the methodology described above. Drugs billed to DME MACs are still priced locally, albeit

under the new statutory formula, as applicable. The four DME MACs jointly establish drug payment

limits for drugs that are billed to DME MACs.

The CMS provides an ASP file to each MAC for pricing drugs. Each MAC must accept the ASP files

made available by CMS for pricing bills/claims for any drug identified on the price files.

The ASP drug pricing file shall contain 3 places after the decimal point in the currency field for the

ASP file and contractors shall load the ASP file including 3 places after the decimal point. Contractors

shall carry 3 places after the decimal point for the calculation of the amount due for a line item for each

covered drug, then follow standard rounding procedures in determining the final allowance for that line

item. The final allowed amounts will continue to carry 2 places after the decimal point.

The payment limits included in the revised ASP and Not Otherwise Classified (NOC) payment files

supersede the payment limits for these codes in any publication published prior to this document.