Terrible. Awful. Zero Support. I was so impressed with giffgaff's SIM card ordering process and the fact that they mailed me a SIM card from the UK free of charge. Setup and activate were easy and I was very impressed with the user interface and experience. The huge fail happened when I landed in the UK where I'd be using the SIM card. I had my iPhone 13 set up correctly, and giffgaff showed as my carrier in the upper left corner of my iPhone, however the service didn't work -- at all. I cycled my phone off and on to no avail. I used giffgaff's chat function with their agents and to say they were not helpful would be an understatement. After the fourth message they stopped responding at all. This left me for a week in the UK unable to use my iPhone unless I was connected to WiFi. I am most disappointed that I wasted £15 for a plan that went unused.