It was a good day for Commonwealth Bank shareholders yesterday. 

The big bank booked a record half-year profit of $5.4 billion a 5 per cent jump that defied analysts' expectations.

But the bank's boss Matt Comyn acknowledged conditions remain challenging for some customers and warned the Reserve Bank could hike interest rates again in the next few months.

• GUEST: CBA CEO Matt Comyn
• PRODUCER: Jason Whittaker