The Reserve Bank is today expected to lower the Official Cash Rate by 0.25 per cent as they try to stimulate inflation. Now that's something I'd never had said 20 years ago when inflation was the number one enemy. Now it's our rampaging dollar. It shows what an extraordinary global environment we live in post the GFC and various sovereign debt issues.

So the Reserve Bank will lower the Cash rate but it begs the question, “how will it affect you?”. Will your interest rates go down, either your mortgage or your business lending?

There is a growing disconnect around the world between central bank interest rates and the retail sector. Interestingly it's come to a head just over the ditch where politicians are getting increasingly concerned about banks. The very banks that own most of our banking sector.

Last week the Commonwealth Bank of Australia posted a new record profit. $9.45 billion. Up 3 per cent. And that profit is even after writing off 1.26 billion dollars of bad debts. That's a jump of nearly 30 per cent as the commodity meltdown bites. But despite that it's fair to say the CBA, which owns the ASB here and Colonial Life Insurance, is absolutely raking it in.

But that result came a week after the Australian Reserve Bank dropped their official rate to a record low of 1.5 per cent. Did the banks pass on that cut to their retail customers? No, not in full. Not in full at all. So Labor got stuck in wanting a Royal Commission into banking practices. Even the Prime Minister, Turnbull, a former money trader made tut-tutting noises and urged the banks to pass on the cost of cheap money in full. It's needed to stimulate the domestic economy and defeat deflation.

So let's keep a careful eye on what happens here after today's expected rate cut. And if you're not offered a better deal it might be time to jump up and down. Check your bank charges too.

And here's a simple test to see how banks are making their mountain of money and that's your credit card. In Australia the gap between credit card interest rates and the RBA cash rate is now more than 18% – the largest it has been in 27 years since data has been kept. Its still 20 per cent even though the Cash Rate is just 1.5 per cent. And you wonder how banks keep being so profitable in tough times.

So you tell me? What's your credit card rate and how does it make you feel at a time when everyone says how cheap money is, and our Reserve Bank is about to lower the cash rate?