CMS Pub. 100-04, ch. 15, § 20.1.5

The POP determines the basis for payment under the FS, and the POP is reported by its 5-digit

ZIP Code. Thus, the ZIP Code of the POP determines both the applicable GPCI and whether a

rural adjustment applies. If the ambulance transport required a second or subsequent leg, then

the ZIP Code of the POP of the second or subsequent leg determines both the applicable GPCI

for such leg and whether a rural adjustment applies to such leg. Accordingly, the ZIP Code of

the POP must be reported on every claim to determine both the correct GPCI and, if applicable,

any rural adjustment. Part B contractors must report the POP ZIP Code, at the line item level, to

CWF when they report all other ambulance claim information. CWF must report the POP ZIP

Code to the national claims history file, along with the rest of the ambulance claims record.

A. No ZIP Code

In areas without an apparent ZIP Code, it is the provider’s/supplier’s responsibility to confirm

that the POP does not have a ZIP Code that has been assigned by the USPS. If the

provider/supplier has made a good-faith effort to confirm that no ZIP Code for the POP exists, it

may use the ZIP Code nearest to the POP.

Providers and suppliers should document their confirmation with the USPS, or other

authoritative source, that the POP does not have an assigned ZIP Code and annotate the claim to

indicate that a surrogate ZIP Code has been used (e.g., “Surrogate ZIP Code; POP in No-ZIP”).

Providers and suppliers should maintain this documentation and provide it to their contractor

upon request.

Contractors must request additional documentation from providers/suppliers when a claim

submitted using a surrogate ZIP Code does not contain sufficient information to determine that

the ZIP Code does not exist for the POP. They must investigate and report any claims submitted

with an inappropriate and/or falsified surrogate ZIP Code.

If the ZIP Code entered on the claim is not in the CMS-supplied ZIP Code File, manually verify

the ZIP Code to identify a potential coding error on the claim or a new ZIP Code established by

the U.S. Postal Service (USPS). ZIP Code information may be found at the USPS Web site at

http://www.usps.com/, or other commercially available sources of ZIP Code information may be

consulted.

• If this process validates the ZIP Code, the claim may be processed. All such ZIP Codes

are to be considered urban ZIP Codes until CMS determines that the code should be

designated as rural, unless the contractor exercises its discretion to designate the ZIP

Code as rural. (See Section §20.1.5.B – New ZIP Codes)

• If this process does not validate the ZIP Code, the claim must be rejected as

unprocessable.

The contractor shall use the following remittance advice messages and associated codes when

rejecting/denying claims under this policy. This CARC/RARC combination is compliant with

CAQH CORE Business Scenario Two

Group Code: CO

CARC: 16

RARC: N53

MSN: N/A

B. New ZIP Codes

New ZIP Codes are considered urban until CMS determines that the ZIP Code is located in a

rural area. Thus, until a ZIP Code is added to the Medicare ZIP Code file with a rural

designation, it will be considered an urban ZIP Code. However, despite the default designation

of new ZIP Codes as urban, contractors have discretion to determine that a new ZIP Code is rural

until designated otherwise. If the contractor designates a new ZIP Code as rural, and CMS later

changes the designation to urban, then the contractor, as well as any provider or supplier paid for

mileage or for air services with a rural adjustment, will be held harmless for this adjustment.

Providers and suppliers should annotate claims using a new ZIP Code with a remark to that

effect. Providers and suppliers should maintain documentation of the new ZIP Code and provide

it to their contractor upon request.

If the provider or supplier believes that a new ZIP Code that the contractor has designated as

urban should be designated as rural (under the standard established by the Medicare FS

regulation), it may request an adjustment from the A/B MAC (A) or appeal the determination

with the A/B/MAC (B), as applicable, in accordance with standard procedures.

When processing a claim with a POP ZIP Code that is not on the Medicare ZIP Code file,

contractors must search the USPS Web site at http://www.usps.com/, other governmental Web

sites, and commercial Web sites, to validate the new ZIP Code. (The Census Bureau Web site

located at http://www.census.gov/ contains a list of valid ZIP Codes.) If the ZIP Code cannot be

validated using the USPS Web site or other authoritative source such as the Census Bureau Web

site, reject the claim as unprocessable.

C. Inaccurate ZIP Codes

If providers and suppliers knowingly and willfully report a surrogate ZIP Code because they do

not know the proper ZIP Code, they may be engaging in abusive and/or potentially fraudulent

billing. Furthermore, a provider or supplier that specifies a surrogate rural ZIP Code on a claim

when not appropriate to do so for the purpose of receiving a higher payment than would have

been paid otherwise, may be committing abuse and/or potential fraud.

D. Claims Outside of the U.S.

The following policy applies to claims outside of the U.S.:

• Ground transports with pickup and drop off points within Canada or Mexico will be paid

at the fee associated with the U.S. ZIP Code that is closest to the POP;

• For water transport from the territorial waters of the U.S., the fee associated with the U.S.

port of entry ZIP Code will be paid;

• Ground transports with pickup within Canada or Mexico to the U.S. will be paid at the

fee associated with the U.S. ZIP Code at the point of entry; and

• Fees associated with the U.S. border port of entry ZIP Codes will be paid for air transport

from areas outside the U.S. to the U.S. for covered claims.

As discussed more fully below, CMS will provide contractors with a file of ZIP Codes that will

map to the appropriate geographic location and, where appropriate, with a rural designation

identified with the letter “R” or “B.” Urban ZIP Codes are identified with a blank in this

position.