About Transactions

This guide describes general characteristics of transactions in the Galileo system. For an explanation of how card transactions work specifically, consult About Card Transactions.

In the Galileo system, “transaction” describes any movement of funds into or out of a customer account. Transaction types include payment-card transactions, direct deposits, ACH transfers, cash loads, ATM fees, and other types of money movement.

Transactions are central to any banking app. Your customers expect to use your product to create transactions and to see a history of their transactions. You can enable them to do both by using Galileo's API.

Consult Finding Transaction Data to see where each transaction type is visible.

Creating transactions

Transactions are created in two primary ways:

  • Using the API — The transaction can be initiated by:
    • Your customers on your web site or mobile app, such as an ACH credit
    • You, according to your business logic, such as assessing a fee
  • Outside the API — The transaction can be initiated by:
    • A card reader at a point of sale or ATM, such as a card purchase at a merchant site. See About Card Transactions for more information.
    • An external depositing entity, such as an employer making a direct deposit. See About ACH for more information.
    • An external debiting entity, such as a utility automatically withdrawing a billing amount

For the transactions that are created outside of your programmatic control, you can be notified of them by consuming the Auth API webhook or the Events API webhook, obtaining Transaction History via API, or consuming the daily RDFs.

See About the Events API and About the Raw Data Files (RDFs) for more information.

Classifying transactions

Each transaction is classified by its activity category and transaction type, also called the otype.

Activity category

All transactions belongs to one of four activity categories:

  • Authorization/Settlement — A transaction that occurs over a card network's rails (system), such as when a cardholder initiates a purchase at a store.
  • Payment — A transaction by which funds are moved into a customer account, originating with the Program API or with an external source such as a paycheck deposit.
  • Adjustment — A transaction used to modify the customer's balance for various operational purposes, either a credit or debit, originating with the Program API or a direct debit from outside the API, such as an ACH transaction.
  • Fee — A transaction that charges a cardholder for a particular service, which may originate with the Program API or by an automated process.

Click the link for each category to see details on that category.

The authorization/settlement category is broken down into multiple activity types, whereas payments, adjustments, and fees have only one activity type each. The activity types in the authorization/settlement category differentiate among card networks such as Mastercard and Visa and types of transactions such as authorizations, expired authorizations, backouts and settlements.

Galileo uses two capital letters to represent activity types. Some common authorization/settlement activity types are:

CodeActivity type
AUMastercard Banknet authorization
SEMastercard Banknet settlement
DBMastercard debit authorization
SDMastercard debit settlement
VIVisa authorization
VSVisa settlement
ISVisa Interlink settlement
PLVisa Plus settlement
EXExpired authorization

Non-network activity types are represented as follows:

CodeActivity type



For a list of all activity types consult the Activity Type enumeration.

Transaction type

Each of the activity type categories is divided into more specific transaction types, often called otypes. For example, a payment could be a direct deposit, a cashier's check, or a cash load, among others.

An otype consists of one to four characters, can contain letters or numbers, and is case sensitive. For example, in the adjustment activity category, DC is a Discover chargeback whereas dc is a direct-load reversal.

An otype is unique only within the activity category. For example, Z is a bill-payment check in the adjustment activity category and a merchant credit in the authorization/settlement activity category.

This table contains some authorization/settlement otypes that are common to all networks:

5Mastercard Banknet settlement
8Mastercard Banknet settlement for mobile wallet or peer-to-peer cash transfer
ARetail sale
BBalance inquiry
CPreauthorization completion
WATM withdrawal

See the Transaction Types enumeration for a list of authorization/settlement otypes. For payments, adjustments, and fees, the otypes are in the Funds Flow document that Galileo provides you. You can see your custom otypes in the CST under System Administration > Web Services > Provider Transaction Types with Right ID 165.

Transaction codes

A transaction code (often designated trans_code) is a combination of an activity type (the first two characters) and an otype (the remaining characters). This table shows some common transaction codes.

CodeActivity typeotype
AUAAU — Mastercard Banknet authorizationA — Retail sale
SE5SE — Mastercard Banknet settlement5 — Settlement
DBADB — Mastercard debit authorizationA — Retail sale
SDASD — Mastercard debit settlementA — Retail sale
VILVI — Visa authorizationL — Preauthorization
ISCIS — Visa Interlink settlementC — Completion
PMVTPM — PaymentVT — Visa Money Transfer
ADHAD — AdjustmentH — Chargeback
FE0013FE — Fee0013 — Domestic ATM withdrawal fee

Because of this structure, a transaction code can be easily deconstructed to obtain the activity type and otype.

Activity type and transaction type in the Galileo system

The transaction code and its component parts are represented differently by different aspects of the Galileo system.

Program API

The program APIs return the transaction code, activity type and otype in these fields:

Get Account OverviewXX
Get Authorization HistoryX
Get Transaction HistoryXX
Get All Transaction HistoryXXX

Use the trans_code for reconciliation with the TRANSACTION CODE/TYPE field in the Posted Transactions RDF.

Events API

Authorization, Settlement, and Transaction Events messages break out the transaction code into two fields: activity type (act_type) and transaction type (otype).

Auth API

The activity type must be derived from the auth_type and subnetwork parameters. For example, if auth_type: Auth and subnetwork: Mastercard Debit Switch, then the activity type is DB (Mastercard Debit Authorization).

The otype is in the transaction_type parameter. However, the value will be a transaction-type description rather than the code. For example, you would see transaction_type: Balance Inquiry instead of B.


The Posted Transactions RDF includes the transaction code as TRANSACTION CODE/TYPE. The transaction code may be deconstructed to obtain the activity type and otype. Use the lookup file included with the RDFs to obtain the transaction code description.



The TRANSACTION CODE field in the Authorized Transactions RDF does not contain the trans_code. It contains a numeral that specifies the type of authorization that was requested. See the Authorization types list in the Transaction Types enumeration.


On the All Transactions screen in the CST, the Type column contains the activity type description, and the Type field in the Details column contains the otype.

This table summarizes the way transaction codes are represented in the Galileo system.

Galileo systemActivity type / otype
Get Account Overview
Get Transaction History
Get All Transaction History
Events APIact_type / otype
Auth APIsubnetwork+ transaction_type
CSTType column / Type field in the Details column

Transaction properties

Among a transaction’s properties, the most important are the identifier, amount, timestamp, and the category-specific properties.


Galileo transaction IDs are integers, sequentially assigned according to the transaction type. See Transaction IDs for an explanation of how Galileo assigns IDs and how to devise unique identifiers for your system.


The amount or amt field indicates how much money is involved in the transaction and specifies which direction the funds are moving: a positive amount means that money is entering the customer account (credit) and a negative amount means that money is leaving the account (debit).

The sign for the amount is represented differently in different Galileo systems.


In the RDFs, the minus sign precedes the amount, or for credits there is no sign, for example: -30.25 for a debit or 23.67 for a credit.

Auth API

In the Auth API the amount does not have a plus or minus sign. You must determine whether it is positive or negative by the transaction type. First, multiply the amount by –1, then multiply again by –1 for each of these conditions:

  • auth_type: Reversal
  • transaction_type: Merchant Credit
  • transaction_type: Payment

Program API

Amounts that credit a cardholder account have no sign, and amounts that debit an account are are preceded by a hyphen: 35.41 and -254.78.

Events API

Most events have no sign in the amount field, so you must infer whether the amount is credited or debited by the event type. For example, a BAUT: auth event is a debit whereas AAPM: auth_payment is a credit. On the other hand, FREV: fee_reversal contains a negative number because it is reversing out a fee. These exceptions are noted in each Event description.


Depending on the data source and the activity category, there may be one or two timestamps. If there are two timestamps showing different times, the earlier timestamp shows the time the transaction was initiated and the later timestamp shows when it was posted. For authorization/settlements, the first timestamp is the authorization and the second the settlement. If the two timestamps show the same time it means the transaction was posted immediately.



All Galileo timestamps are in the America/Phoenix time zone (MST -07:00), a time zone that does not observe daylight saving

Category-specific properties

Other properties of the transaction may be important, depending on which activity category the transaction belongs to. For example, mcc (merchant category code) is pertinent to authorizations and settlements, and related_transaction is pertinent to pending fees.

Linking transactions

Some transactions pass through multiple phases before completion, such as most card transactions (authorization/settlement), whereas fees are often connected to transactions that may or may not have originated on the card networks. The fields in this table can help you link related transactions.

Transaction typeLinked toLinking field
Reversal ID
Settlement or postingAuthorization or non-network transactionauth_id
FeeAny transactionrelated_transaction

The linking fields for authorizations have different names in different systems, but they all contain the same value:

The linking fields contain the auth_id of a previous authorization in these circumstances:

  • The merchant performs incremental authorizations for a single purchase. Each authorization has the auth_id of the previous authorization in the chain.
  • An authorization or preauthorization is reversed. The reversal has the auth_id of the transaction to reverse in the linking field.
  • A preauthorization is followed by a completion. The completion contains the auth_id of the original preauthorization.
  • You charge a fee for a card transaction, such as an ATM fee. The fee is broken out separately from the settlement in the Posted Transactions RDF, and the fee entry has the auth_id of the original authorization. (The original authorization has the fee included in the amount instead of broken out.)

For authorization/settlement transactions the auth_id and source_id contain the same value. For a transaction that does not originate on a card network, the auth_id may or may not be present. When the auth_id is present, the source_id is often different, because it maps to the specific transaction type such as a payment ID or fee ID.

For example, a Maestro load payment (trans_code: PMMX) can have an auth_id in the Authorized Transactions RDF that maps to the auth_id in the Posted Transactions RDF, but the source_id is different, because it maps back to the payment ID. See Scenario 17: Card Load (Maestro) for an example.

In the CST, the ID field always maps to the source_id.

In the Base RDFs, the mapping is as follows:

  • PRIOR ID — Contains the payment, adjustment, or fee that links to the current transaction.
  • REVERSAL ID — Contains the AUTHORIZATION CODE of the previous authorization in the series.

For examples of linking fields in use, see these card transaction scenarios:

Blocking transactions

Depending on the use case for a particular product, you may want to block certain types of transactions from taking place, or you can block transactions depending on the status of the account. In some cases you need to set product parameters for the block, and in other cases you use the Program API.

Card transactions

You can block card transactions using a variety of methods, depending on the type to block.

All card transactions

The fastest way to block all card transactions is to put a freeze on the card. Such a block does not affect ACH, billpay, Program API transactions, or fees.

PIN or signature transactions

You might decide that you want to block all PIN transactions or all signature (non-PIN) transactions. The PBLOK parameter controls this kind of block.

Card loads

Card loads that arrive over network rails are blocked by default, and so they must be enabled by setting one or more of these parameters:

  • DCLD — Discover loads
  • MCLD — Mastercard and Maestro loads
  • STRLD — STAR loads
  • VSALD — Visa ReadyLink and Visa Money Transfers

After you have enabled any of these card loads, you can block the loads by account status by populating the BLKLD parameter with the statuses to block.

Transaction types

You can block various transaction types using the Set Account Feature endpoint.

Transaction to blockfeatureTypefeatureValue
Card not present6N
Card not present and card present (allow mobile wallet only)20Y
Card present21Y
Mobile wallet22Y
ATM withdrawals9Y
Cash advances10Y


Blocking by MCC means that when an authorization request arrives for a card transaction, Galileo checks the MCC, and if the MCC is on your blocklist, Galileo denies the transaction.

You can set an MCC block in these ways:

  • During initial product configuration. The MCC block applies to all cards with that prod_id.
  • On a per-account basis, using Account-Level Authorization Controls. These account-level controls are applied in addition to the product-level controls.

By merchant ID

To block transactions from a particular merchant, you can block the merchant ID, which identifies a specific point of sale. You can create merchant ID blocks during product setup, or if you are using Galileo's fraud-detection engine, merchant ID blocks will be added automatically. To apply a merchant ID block at the account level, use Account-Level Authorization Controls, which override product-level MCC and merchant ID controls.

By country

During initial product setup you can determine which transactions to block by originating country code, such as OFAC countries. You can also set the BLKTM parameter to block transactions from those countries only at certain times of day. With the NOBLK parameter you can specify which country codes should never be blocked.

To block all international transactions for an account, call Set Account Feature with these parameters:

  • featureType — 8
  • featureValue — N

Consult International merchants in About Card Transactions for information on how a transaction is considered to be domestic or international.

API-based money movement

To block transactions that are initiated by the Program API (Create Payment, Create Adjustment, Create Account Transfer), input the account statuses in the STPLD product parameter. You can input all possible account statuses, or you can input a subset.

ACH transactions

If your program supports ACH transactions, you can block ACH transactions as follows:

Transaction to blockHow to block
Incoming ACH credit (funds going into the customer account)Set ACCRD
Incoming ACH debit (funds going out of the customer account)Set ACDBT
Incoming ACH credit by account statusPopulate ACSTS with the statuses to block
Incoming ACH debit on an inactive accountSet ACHCA to stop the debit when the account is not in status: N.

Transaction history

See the Transaction History guide for the method to retrieve an account’s transaction history.