Diagram explaining how an offline chip card transaction is approved without contacting the bank

An offline transaction is one where, when a transaction is made at a POS with a chip card, the transaction is approved by the card and the POS themselves, by their own decision, without going to any system (the card's issuer or the POS's acquirer).

When do the issuer and the acquirer find out about offline transactions?

The acquirer;

It finds out about the transaction when the offline transaction is sent by the POS to the acquirer.

The issuer; 

  • If the transaction is on-us (the issuer and the acquirer are the same bank), when the transaction is forwarded by the POS to the bank
  • If the transaction is not-on-us (the issuer and the acquirer are different banks), it finds out about the transaction through the clearing file (the incoming file).

Is there a limit for offline transactions?

The offline transaction limit was updated to 750 TL as of July 1, 2022. The cardholder can raise this limit if they wish.

Do all transactions under 750 TL take place offline?

No. First, the POS and the card must decide that the transaction should be approved offline.

The POS generally holds parameters similar to the following ones, related to offline transactions.

  • Go online after X offline transactions
  • Go online after a total of Y TL in offline transactions
  • Go online every Z minutes

For example, on a POS where the following parameters are defined;

  1. Go online after 5 offline transactions
  2. Go online after a total of 600 TL in offline transactions
  3. Go online every 10 minutes — if this parameter is defined;

The POS can hold at most 4 offline transactions pending. Even if the card approves going to offline authorization on the 5th transaction, the POS will route the transaction online instead.

Let's assume a 300 TL offline transaction is already pending on the POS. When a 500 TL offline transaction is attempted, because of the parameter in item 2, the total amount would exceed 600 TL, so the 500 TL transaction is routed to online authorization.

According to parameter 3, an offline transaction can remain pending on the POS for at most 10 minutes. At the 10-minute mark, all offline transactions pending on the POS are forwarded to the bank's host.