Banks are in business to make money, and basically they do that in two ways: by charging you for services and by using the money you have placed with them.

The balance between these two seems to be shifting. Not so long ago, banks charged for just about everything: their charging systems were arcane and intricate, and a casual observer might think they were designed to confuse customers.

Amazingly, some of this attitude persists. Take a look at the tariffs for the bigger banks: they often run to several pages, frequently with a range of prices for apparently similar services delivered in slightly different ways. Businesses tend to use more banking services than the individual, so there are more charges that the bank can apply. And for some businesses there may less incentive to check the details; forensic analysis can take some time, and most of us need to get back to earning money.

But competition has produced a much better banking environment for the smaller business. Nearly all the banks have good starter deals and/or all-inclusive fixed monthly fees. Stick to the limits on the number of cheques you can issue or the number of deposits you can make, and the cost of your banking should be predictable and checkable.

Those deals mean that the banks are looking more to the alternative way of making money, using the funds you have deposited with them to make short-term investments, normally on the currency markets.

This is particularly profitable if the bank doesn't have to give you something in return: interest, for instance. There's a lot more attention on rates of interest for consumer accounts, but business current accounts don't normally earn much interest at all (and some are still completely interest-free).

You can't stop the bank using your money to make money for itself. But you can make your money work as hard as possible. Here are the top three tips:

· Minimise charges by reducing the number of transactions (use one paying-in slip for as any cheques as possible), staying clear of branches - deposits at an ATM are usually cheaper. Avoid cheques in favour of automated payments, such as standing orders and BACS transfers.

· Avoid unauthorised overdrafts. In particular, make sure payments to you have cleared before you start writing cheques. You can set up BACS transfers for a particular date in the future, too.

· Move surplus funds to a high-interest deposit account as soon as possible. You may be able to automate this, so that balances over a certain level are automatically transferred.