A debit card transaction will usually be debited from your account on the following working day. However, if the amount of the transaction is above the floor limit of that retailer, the card issuer will earmark the funds on your account at the time the transaction is made. The time it takes for the money to reach the retailer is dependent upon the terms of the contract with their merchant qcquirer (bank).

You should be aware that if you buy foreign currency or travellers cheques using your debit card it may be treated like a cash transaction so your bank may charge you. If they do, as with all competitive charges, it will be outlined in your terms and conditions. The travel exchange bureau/provider may also charge you for using your debit card but this should always be made clear to you up front.

Your protection is greater if you use a credit card and the transaction is for an amount between £100 and £30,000. This is because the credit card issuer is jointly liable under Section 75 of the Consumer Credit Act if the goods received are faulty or if they are not received at all, e.g. if the company goes out of business. In these circumstances the credit cardholder will be able to get their money back from their card issuer but the debit cardholder probably wouldn't.