Developer's Guide

Processors Requiring Additional Transaction Parameters
American Express
A
68 Payflow Pro Developer’s Guide
American Express Additional Credit Card Parameters (CAPN)
NOTE: You should start coding to the CAPN parameters if you want to be able to impact what
appears on AMEX statements and reports. With a few exceptions, most merchants in
the United States follow CAPN requirements; international merchants do not. If you
are not sure whether you should make the coding changes, contact Customer Service.
See “How to Contact Customer Support” on page 9 for contact information.
American Express Phoenix accepts the following parameters to meet CAPN requirements.
TABLE A.1 American Express CAPN parameters
Parameter Description Required Type Length
Retail Transaction Advice Addendum Parameters (for SWIPE transactions)
L_DESCn Description of this line-item (n is a line item
number from 1 to 6)
No Alpha-
numeric
19
L_AMTn Amount of this line-item (n is a line item number
from 1 to 6)
Must include a decimal and be exact to the cent
(42.00, not 42) and exclude comma separators
(1234.56 not 1,234.56)
Examples: tip=3.00, convenience charge=2.00
No Numeric 12
L_QTYn Quantity of this line-item (n is a line item number
from 1 to 6)
No Numeric 3
Internet Transaction Data Parameters
EMAIL Account holder’s email address No Alpha-
numeric
60
PHONENUM Account holder’s telephone number No String 20
PHONETYPE Telephone company provided ANI information
identifier digits indicating the telephone call type
Examples: cellular (61-63), payphone (27)
No Alpha-
numeric
2
CUSTHOSTNAME Name of the server that the account holder is
connected to
Example: PHX.QW.AOL.COM
No Alpha-
numeric
and
special
characters
60
CUSTBROWSER Account holder’s HTTP browser type
Example:
MOZILLA/4.0~(COMPATIBLE;~MSIE~5.0;~W
INDOWS~95)
No Alpha-
numeric
and
special
characters
60