BNZ is apologising for the meltdown yesterday that locked people out of ATMs, EFTPOS, internet banking and even physical bank branches for several hours yesterday.

It was caused by a power outage in Australia.

The National Australia Bank - BNZ's parent company - is promising to compensate its customers if they suffered a financial loss.

But BNZ here is wording what it will do differently.

It says it is working through how best to support customers who have been affected.

BNZ says this will include working with customers who experienced direct financial loss due to the outage to ensure they are not unfairly impacted.