FNB banking app users will no longer need data to access the app via their smartphones from 1 July 2017.
FNB has reached an agreement with all major mobile network operators in South Africa to zero rate access to the app.
The bank also offers free Wi-Fi in most FNB branches for customers to download the app, it said.
The banking app includes FNB’s Smart inContact service, which notifies customers of transactions for free.
Android and iOS users can also now authenticate themselves in the app using Fingerprint ID.