The Payment Services Regulations 2009 (PSR) define the law relating to banking and credit card matters, including how unauthorised banking and card transactions must be dealt with. 

These principles are reflected in the Financial Conduct Authority (FCA) Handbook called entitled Banking: Conduct of Business and Sourcebook (BCOBS) that banks and card providers must follow.

Summary

The Payment Services Regulations 2009 protect you if there is an unauthorised transaction made on your credit or debit card, for example if it was stolen or you were victim to a scam.  

As long as you weren't acting negligently, you should be able to get your money back. 

If your credit or debit card is lost or stolen and then used to buy something you should get the disputed sum paid back to you. 

If your card provider can show that you failed to take reasonable steps to protect your security features e.g. your card pin number then it can make a £50 deduction from the refund - it can’t though make this deduction if the transaction was made after you had reported the card lost or stolen.

If your credit or debit card provider can show that you acted fraudulently or you were grossly negligent then it would have grounds to refuse to refund any of the disputed sum.  

The Payment Services Regulations can help if there is a transaction on your credit card that you know nothing about.

If the card has not been lost or stolen but someone else uses the card details to buy something, for example if a card is cloned or someone uses details you gave to a retailer when buying an item over the phone or through the internet, then the Payment Services Regulations mean you should be refunded in full. 

Again, if it can be shown that you had acted fraudulently or were grossly negligent then the card provider can refuse to credit the sum back.

If the card is used before you received it then you should be refunded in full.