MONEY TALK By Matt Brown Senior researcher, Which? magazine

The UK's biggest banks are busy announcing bumper profits.

Collectively, it's estimated that UK banks are making more than �30bn - that's more than �3m an hour.

But their gain need not be at your expense. There are lots of simple ways to make sure you aren't losing out, while pocketing a few extra pounds for yourself, too.

Current accounts

If you are one of the seven in 10 people who still have a current account with the big four banks - Barclays, HSBC, Lloyds TSB and NatWest - then you may be missing out on the best rate of interest.

In the latest Which? survey, 90% of respondents who had switched current account provider said it was straightforward

Most of the current accounts offered by the big four pay about 0.1% interest, which compares very unfavourably with the 5% available from Alliance & Leicester.

What is more, if you regularly slip into the red it is important to check your overdraft rate too.

Nationwide currently have the lowest overdraft rate available - 6.75% - whereas Lloyds TSB charges up to 18.2%.

Cahoot automatically gives its customers a �250 interest free overdraft, great for borrowing small sums of money.

Banks charged a staggering �3bn for unauthorised overdraft charges last year.

So, if you have overspent, contact your bank as soon as possible.

You may be able to set up a small temporary overdraft or increase your limit. Complain if you feel you have been harshly penalised.

If after looking at how your current account shapes up you decide to switch provider, the good news is that it is easy to do so.

In the latest Which? survey, 90% of respondents who had switched current account provider said it was straightforward.

Credit Cards

Banks make about �400m a year by charging customers who pay credit card bills late or exceed credit limits

If you use a credit card to borrow, you should make use of 0% deals - they can save you hundreds of pounds.

But don't be caught out by sneaky tricks.

Many credit card companies rely on customers forgetting to move their balance once the interest free period runs out. One card charges up to 18.9% once its 0% deal runs out.

Even if you always pay off your credit card balance in full, it's still worth shopping around.

Some cards give you 'cashback' on everything you spend (usually 0.5% to 1%).

Some are less generous for higher spenders; with others you get a higher percentage if you spend more.

And keep an eye on your card's cashback rate: lots of issuers slashed their rates recently.

TIPS FOR BEATING THE BANKS Be prepared to switch current account Make use of 0% credit card offers Do not get caught out by credit card late repayment penalties Avoid payment protection insurance on loans Take advantage of introductory savings bonus rates

Like unauthorised overdraft charges, banks make lots of money from credit card penalty charges.

Banks make about �400m a year by charging customers who pay credit card bills late or exceed credit limits.

So, where possible, make payments by direct debit and keep a watchful eye on your credit limit.

Personal loans

You will find big differences in rates between personal loans too.

But it is not just the interest that makes loan firms money - it is the extras. Personal loan companies make at least �1bn in commission from selling payment protection insurance (PPI) with personal loans each year.

Which? has found that adding PPI on to a three-year �5000 HSBC loan would increase the total cost by �1,000.

PPI is designed to pay your loan or credit card payments if you are unable to work.

However, it is expensive, gives limited cover and can be useless for the self-employed or those on contracts.

Many companies automatically include PPI in quotes so do not get caught out.

Given the chance of you needing, or being able to, make a claim is fairly low, you would be better off saving the money or buying an income protection policy, which is better because it gives you money to use for any purpose and may pay out for longer.

Savings

UK savers could earn an extra �10bn in interest each year by switching savings to the best rates available. That is more than �360 each.

Best-buy instant access and notice accounts are paying the highest interest rates we have seen for three years.

Take advantage of introductory bonus rates too - these are higher rates offered to new customers for an initial period. But don't forget to move your savings once the bonus rate expires.