If you card is lost or stolen, you'll need to report it immediately to your bank or credit card issuing company. Remember to ask about an emergency replacement if you need one. You can use the following numbers (note: Visa and Mastercard will accept loss reports for all of their cards):
American Express 01273 696 933
Bank of Scotland / Halifax (HBOS) 0845 604 7000
Barclaycard 01604 230 230
HSBC 0845 600 7010
Lloyds TSB 0800 096 9779
Mastercard (report any mastercard) 0800 96 4767
NatWest 0870 600 0459
Royal Bank Scotland 0800 252 083
Visa (report any visa card) 0800 89 1725
London Hotels (these links are to another website)