Malta is an interesting place for card payments.

Most retailers have two separate card machines. One provided by HSBC for their local card customers who have a Quikcash card (not a visa/mastercard and only useful in Malta and in HSBC machines elsewhere). Their machines also process Visa etc.

The other machine will be by BoV (Bank of Valletta). Since BoV issue an Amex card, all of their machines accept Amex, which means an amazingly high proportion of retailers, including small shops will process an Amex payment, unlike most of Europe including the UK.

However, to get back on track with this thread, when presenting an American Express card, you will need to insist on using the BoV machine and swiping the card. As although I have UK issued Amex Platinum and BA Amex cards with PINs, the machine will only work in swipe mode.