American Express Mass Transit Model

The American Express mass transit transaction model that is American Express PAYG with delayed authorization using Expresspay transit policy. See American Express Pay As You Go.
Characteristics of the American Express PAYG Model
Characteristic
PAYG with Delayed Authorizations
Dedicated transit merchant category code (MCC) values
M
Population of transit access terminal indicator
M
Decline expired cards
M
Decline expired cards
M
Deny list capability
M
Transaction aggregation
O
Account status check
M
Enhanced risk mitigation
O
Application transaction counter (ATC) synchronization
O
PAN translation
O

American Express Pay As You Go

The American Express Pay As You Go (PAYG) model is a delayed authorization using the Expresspay transit policy. These are the key characteristics of this model:
  • Journeys are multimodal.
  • Fares are based on distance.
  • Points of entry are contactless.
  • Accounts are verified with an authorization for a nominal amount or the maximum fare amount.
  • The deny list is checked so that cardholders with previously declined transactions can be blocked.
  • Data can be authenticated offline to confirm that the card is valid.
  • Multiple card taps and fares can be aggregated into a single payment.
  • The deny list is automatically updated every 20 minutes.
  • The back office records all trips and fares in order to reconstruct journeys and calculate the final fare.
  • When the nominal amount authorization is declined, debt recovery can be performed.
  • Standard follow-on payment services can be used to capture, reverse, or void transactions.

Figure:

Pay As You Go Delayed Authorization Model
Diagram of the American Express Pay As You Go Aggregated transaction model.

American Express Authorization and Capture Options

You have two options for handling authorizations and captures.
Option 1:
  1. Send an authorization request for a nominal amount.
  2. During the travel period, collect the rider's tap data to calculate the aggregated fare.
  3. When the floor limit is reached, send a capture to collect the accumulated amount.
  4. After completing the capture, return to step 1 to handle subsequent trips and journeys.
Option 2:
  1. Send an authorization request for a nominal amount.
  2. During the travel period, collect the rider's tap data to calculate the aggregated fare.
  3. If the number of trips exceeds the floor limit, send a delayed online authorization.
  4. Upon completion of the delayed online authorization, return to step 1 to handle subsequent trips and journeys.
Implement the version that suits your business model. However, American Express requires your payment technology partner (PTP) to support nominal and full value authorizations during the L3 certification.