Most concern about direct debits revolves around the direct debit guarantee, and what to do when things go wrong.

I have included the direct debit guarantee here.

You can see that

• "With a variable direct debit the originator must provide enough advance notice of the amounts and dates of payment, or any changes to them, in sufficient time to allow the customer to raise any queries prior to payment. This is defined as at least ten working days from receiving the notification."
   
• "Should any money be taken in error, then the customer's bank or building society must, on request, make an immediate [our stress] refund to the customer's account."
   
• "This covers situations where the originator has not given the required advance notice regarding a change of amount or date. It also protects customers should an incorrect amount be debited or if a debit occurs earlier than the specified, agreed date, or in error."

And if you want to cancel a direct debit

• "A direct debit can be cancelled at any time by the customer informing their bank or building society, usually in writing. It is also advisable to inform the supplier as well, but this is not obligatory as the bank or building society will also do it."

In essence, you let companies debit your bank account. This is cheaper for companies and banks, and sometimes you get a discount off a bill for paying by direct debit.

In return, if you tell tha bank something is wrong, they must give you the money back, and leave you to sort it out with company which originated the debit.

If an error - by the originator or by the bank - has caused you extra expense (perhaps by causing you to go overdrawn), the bank must put you back in the position you would have been in if the mistake had not happened. Whether this cost is borne by the bank or passed on to the originator is no concern of yours.

So, if there is a mistake or a dispute, complain at once. Our guide to complaining is here. Make sure you get full and prompt recompense.

The official message about direct debits is buried in frames in the site of the the Association for Payment Clearing Services.

There is a page about paperless direct debits here.