US · guidance
CMS Pub. 100-04, ch. 23, § 40.2
A/B MAC (B) Record Layout for Clinical Laboratory Fee Schedule
PM AB-01-162, AB-02-163
The instructions for each annual update contain the actual data set name for that year. The Data Set Name is
included with each annual update instructions.
Data Element Name Picture Location Comment
HCPCS Code X(05) 1-5
A/B MAC (B)
Number
X(05) 6-10
Locality X(02) 11-12 00 = Denotes Single A/B MAC (B)
State
01 = North Dakota
02 = South Dakota
20 = Puerto Rico
40 = New Hampshire
50 = Vermont
60% Local Fee 9(05)V99 13 - 19
62% Local Fee 9(05)V99 20 - 26
60% Natl Limit Amt 9(05)V99 27 - 33
62% Natl Limit Amt 9(05)V99 34 - 40
60% Pricing Amt 9(05)V99 41 - 47
62% Pricing Amt 9(05)V99 48 - 54
Gap - Fill Indicator X(01) 55 - 55 0 = No Gap-fill Required
1 = A/B MAC (B) Gap-fill
2 = Special Instructions Apply
Modifier X(02) 56 - 57 Where modifier is shown, QW
denotes a CLIA waive test.
Filler X(03) 58 - 60
History
(Rev. 1, 10-01-03)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
b6222093c286709be77f4c5f1e77b9266adc9178e59bd564ff46c7978192355a
The link goes to the issuing authority’s own document — the one we read to produce this record. Where a source publishes whole titles rather than sections, your browser may need a moment to jump to the provision.
Unofficial copy of government-published law, reproduced from official sources with full provenance. Not an official publication; verify against official sources before relying on it in a filing. Records in the 'guidance' corpus, and only that corpus, are sub-regulatory (interpretive guidelines, survey procedures) and are not binding law. Validity bounds follow each jurisdiction's declared temporalBasis.