Bindinglaw

US · guidance

CMS Pub. 100-04, ch. 15, § 20.1.5.1

CMS Supplied National ZIP Code File and National Ambulance Fee

activein force · 2026-08-25 – presentas-observed

Schedule File

(Rev. 2703, Issued: 05-10-13, Effective: 10-01-13, Implementation: 10-07-13)

CMS will provide each contractor with two files: a national ZIP Code file and a national

Ambulance FS file.

A. The national ZIP5 Code file is a file of 5-digit USPS ZIP Codes that will map each ZIP Code

to the appropriate FS locality. Every 2 months, CMS obtains an updated listing of ZIP Codes

from the USPS. On the basis of the updated USPS file, CMS updates the Medicare ZIP Code

file and makes it available to contractors.

The following is a record layout of the ZIP5 file effective January 1, 2009

ZIP5 CODE to LOCALITY RECORD LAYOUT

Field Name Position Format COBOL

Description

State 1-2 X(02) Alpha State Code

ZIP Code 3-7 X(05) Postal ZIP Code

A/B MAC (B) 8-12 X(05) A/B MAC (B)

Number

Pricing Locality 13-14 X(02) Pricing Locality

Rural Indicator 15 X(01) Effective 1/1/07

Blank = urban,

R=rural, B=super

rural

Field Name Position Format COBOL

Description

Beneficiary Lab CB

Locality

16-17 X(02) Lab competitive bid

locality;

Z1= CBA1

Z2= CBA2

Z9= Not a

demonstration

locality

Rural Indicator 2 18 X(01) What was effective

12/1/06

Blank=urban,

R=rural, B=super

rural

Filler 19-20 X(02)

Plus Four Flag 21 X(01) 0 = no +4 extension

1 = +4 extension

Filler 22-75 X(54)

Year/Quarter 76-80 X(05) YYYYQ

NOTE: Effective October 1, 2007, claims for ambulance services will continue to be submitted

and priced using 5-digit ZIP Codes. Contractors will not need to make use of the ZIP9 file for

ambulance claims.

Beginning in 2009, contractors shall maintain separate ZIP Code files for each year which will

be updated on a quarterly basis. Claims shall be processed using the correct ZIP Code file based

on the date of service submitted on the claim.

A ZIP Code located in a rural area will be identified with either a letter “R” or a letter “B.”

Some ZIP Codes will be designated as rural due to the Rural Urban Commuting Area (RUCA)

Score even though the ZIP Code may be located, in whole or in part, within an MSA or Core

Based Statistical Area (CBSA).

A“B” designation indicates that the ZIP Code is in a rural county (or RUCA area) that is

comprised by the lowest quartile by population of all such rural areas arrayed by population

density. Effective for claims with dates of service between July 1, 2004 and December 31, 2010,

contractors must apply a bonus amount to be determined by CMS to the base rate portion of the

payment under the FS for ground ambulance services with a POP “B” ZIP Code. This amount is

in addition to the rural bonus amount applied to ground mileage for ground transports originating

in a rural POP ZIP Code.

Each calendar quarter beginning October 2007, CMS will upload updated ZIP5 and ZIP9 ZIP

Code files to the Direct Connect (formerly the Network Data Mover). Contractors shall make

use of the ZIP5 file for ambulance claims and the ZIP9 file as appropriate per IOM Pub. 100-04,

Medicare Claims Processing Manual, chapter 1 -General Billing Requirements , section 10.1.1 -

Payment Jurisdiction Among A/B MACs (B) for Services Paid Under the Physician Fee

Schedule and Anesthesia Services and the additional information found in Transmittal 1193,

Change Request 5208, issued March 9, 2007. The updated files will be available for

downloading on approximately November 15th for the January 1 release, approximately

February 15th for the April 1 release, approximately May 15th for the July 1 release, and

approximately August 15th for the October 1 release.

Contractors are responsible for retrieving the ZIP Code files upon notification and must

implement the following procedure for retrieving the files:

1. Upon quarterly Change Requests communicating the availability of updated ZIP Code files,

go to the Direct Connect and search for the files. Confirm that the release number (last 5 digits)

corresponds to the upcoming calendar quarter. If the release number (last 5 digits) does not

correspond to the upcoming calendar quarter, notify CMS.

2. After confirming that the ZIP Code files on the Direct Connect corresponds to the next

calendar quarter, download the files and incorporate the files into your testing regime for the

upcoming model release.

The names of the files will be in the following format:

MU00.AAA2390.ZIP5.LOCALITY.Vyyyyr and MU00.AAA2390.ZIP9.LOCALITY.Vyyyyr

where “yyyy” equals the calendar year and “r” equals the release number with January =1, April

=2, July =3, and October =4. So, for example, the names of the file updates for October 2007 are

MU00.AAA2390.ZIP5.LOCALITY.V20074 and MU00.AAA2390.ZIP9.LOCALITY.V20074.

The release number for this file is 20074, release 4 for the year 2007.

When the updated files are loaded to the Direct Connect, they will overlay the previous ZIP

Code files.

NOTE: Even the most recently updated ZIP Code files will not contain ZIP Codes established

by the USPS after CMS compiles the files. Therefore, for ZIP Codes reported on claims that are

not on the most recent ZIP Code files, follow the instructions for new ZIP Codes in §20.1.5(B).

B. CMS will also provide contractors with a national Ambulance FS file that will contain

payment amounts for the applicable HCPCS codes. The file will include FS payment amounts

by locality for all FS localities. The FS file will be available via the CMS Mainframe

Telecommunications System. Contractors are responsible for retrieving this file when it

becomes available. The full FS amount will be included in this file. CMS will notify contractors

of updates to the FS and when the updated files will be available for retrieval. CMS will send a

full-replacement file for annual updates and for any other updates that may occur.

The following is a record layout of the Ambulance Fee Schedule file:

AMBULANCE FEE SCHEDULE FILE RECORD DESCRIPTION

Field Name Position Format Description

HCPCS 1-5 X(5) Level 2 HCPCs

code number for the

service.

A/B MAC (B)

Number

6-10 X(5) Contractor Number

Locality Code 11-12 X(2) Identification of

Pricing Locality

RVU 13-18 9(4)V2 Relative Value

Units set a numeric

value for ambulance

services relative to

the value of a base

level ambulance

service.

GPCI (PE) 19-22 9V3 The GPCI for the

practice expense

portion of the

Medicare physician

fee schedule is used

to adjust payment to

account for regional

differences.

Base Rate 23-29 9(5)V2 A nationally

uniform “base”

amount used to

calculate each

HCPCS’ payment

amount.

Urban Rate 30-36 9(5)V2 Urban Ground/Air

mileage rate.

Rural Rate 37-43 9(5)V2 Rural Ground/Air

mileage rate.

Current Year 44-47 x(4) 4 digit current

effective year.

Current Quarter 48-48 x(1) 1 digit current

effective quarter:

1=January, 2=April,

3=July, 4 =October.

Current Date 49-56 x(8) Current Effective

Start Date.

Filler 57-80 X(26) Future use

History

(Rev. 2703, Issued: 05-10-13, Effective: 10-01-13, Implementation: 10-07-13)

Provenance

Source
cms.gov
Retrieved
2026-08-25
Edition
iom-2026-08-25
Content hash
8966e8b19c0b206a93bc57b9cb93b21abb277b75d0764da8e0f24b6a2d64f54f
View the official source →

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.

Coverage · API docs

Bindinglaw

Point-in-time US law with the receipt attached. Source URL, retrieval time, content hash, and validity dates on every answer.

curl api.binding.law/v1/law/coverage

© 2026 binding.law · a Jubal, Inc. productAttorneys and firms never pay. Ever.
CMS Pub. 100-04, ch. 15, § 20.1.5.1 — CMS Supplied Na… · binding.law