Changes to Transaction Identification with Mastercard - Next Steps 2026

Starting in June 2026, Mastercard is requiring to store the TLID for Economically Related Transactions and to send it starting with October 2026.

As communicated in 2025, Mastercard has introduced the Transaction Link Identifier (TLID), which works alongside the existing Trace ID. The TLID facilitates better consistency in linking and matching related transactions across all the schemes’ platforms. 

In the long run, Mastercard will replace the Trace ID with the TLID. 

Mastercard has identified two categories of related transactions: 

1. Lifecycle Transactions : besides matching an authorization with its clearing(s), the TLID will also connect all transaction types that impact the status of that original authorization—such as reversals, refunds, and chargebacks.

2. Economically Related Transactions : The TLID will link independent payments associated with a single agreement between the merchant and cardholder. This is particularly relevant for transactions like installment and recurring payments, where all subsequent payments should relate back to the original agreement. 

The TLID for Lifecycle Transactions is mandatory since October 2025. As we informed previously, Worldline Acquiring is handling the TLID for Lifecycle Transactions on behalf of you.  

The timeline for using the TLID on Economically Related Transactions is now known and will be as follows:  

• 2nd of June 2026 : Merchants, acceptance gateways or payment facilitators must store the TLID received in a card-not-present CIT (Customer Initiated Transaction) or ASI (Account Status Inquiry) response for future economically related transactions, when the cardholder has agreed for the merchant to store the card on file.

• 23rd of October 2026: Merchants must send the previously retained TLID of the original CIT or ASI with each subsequent economically related transaction. 

What does this mean for you as a Worldline partner?

For 2nd of June 2026 

Be ready to store the TLID returned by Mastercard on the authorization response of relevant transactions. Inform your merchants about this new mechanism.  

This affects all transactions that start an agreement for future card usage, such as storing a card on file, to initiate a subscription or any other recurring transactions. 

IMPORTANT: For agreements existing prior to June 2026, Mastercard is allowing “grandfathering”. Similar to as when the Trace ID was introduced to link CITs and MITs in context of PSD2, the merchant is allowed to pick the TLID from any recurring transaction of this agreement and store it. Mastercard recommends that this previous MIT authorization is an undisputed MIT from at least three months prior. 

There is no need to set up a new agreement with a new fully authenticated CIT after June.  

For 23rd of October 

You start sending the previously retained TLID of the initial CIT or ASI. You will find the relevant field per protocol listed below..

Next Steps

All our protocols and APIs are ready to provide the TLID. Please find below the list of the protocol and API versions that will contain the TLID:

Q & A

1. Do we need to store the TLID for all transactions? 
It is recommended to store it for: 

• Authorizations initiating an agreement for future Merchant Initiated Transactions like subscriptions, installments and unscheduled payments 

• Pre-authorizations that can potentially have an MIT linked to it, like a delayed charge, or a no-show. Typically, transactions related to Travel & Hospitality 

• Nice to store for chargebacks: the TLID could be a better ID to link the chargeback to all the life cycle transactions

2. Which format the Mastercard TLID has? 
The representation of the Mastercard generated TLID is a 22-character UUID and includes case sensitive upper and lower alphabetic, numeric, and special characters in random order (no spaces allowed):

• Upper Case Alpha (A-Z)

• Lower Case Alpha (a-z)

• Numeric (0-9)

• Special Character (- and _ only)

TLID examples:

• aRyU-3Ti981f_6WvBaqM03

• bWyZ3Ci-981f6MvBGa_tN0

Note: Mastercard will drop data that does not meet this specification.

3. Is TLID mandatory as reference on refunds to the original purchase? 
No. At the moment, Mastercard requires the TLID to be provided in the refund authorization response in the clearing. Be reminded that authorization of refunds is an active mandate. 

4. Can a merchant allow to return goods or services in a different store location? 
Yes. In Mastercard’s view, this should not impact the linking, because the refund doesn’t need the TLID of the purchase. 

5. Is it foreseen to use both old Trace ID and new TLID  in parallel? 
Yes. Mastercard will be monitoring the TLID compliance rate to decide when it’s the right moment to start the decommission of Trace ID.  

6. In which field should we send the TLID for economically related transactions? 
Please see above table to understand in which field per protocol to send the TLID. 

7. Should all subsequent transactions contain the TLID received in original transaction?  Or does Worldline recommend only for specific payment types?  
You only need to provide the TLID in the economically related transactions (MITs linked to the original payment). Worldline will take care of the linking for lifecycle transactions. 

8. What can happen if for a subsequent Merchant Initiated Transaction (MIT) we don’t have the TLID? 
For existing subscriptions before June 2026, Mastercard is allowing “grandfathering”. You may store and use a TLID from any of the recurring MITs of such a subscription.

9. When are we able to start testing? 
You can start testing to send the TLID for economically related transactions from July 2026. Please contact us to arrange testing.     

For further questions, please contact your partner manager or  partnership@worldline.com .