New Year's Eve 2003 was the busiest night yet for text messages, but some networks were unable to handle the strain.
Swiss mobile company Sicap tested UK networks by sending out New Year's text messages over the major mobile networks. The average time for delivery was over two hours.
"For many consumers over New Year's Eve the short message service [SMS] they know and love became the slow message service," said Per-Johan Lundin, head of marketing at Sicap, in a statement.
The test found the fastest SMS arriving within 16 minutes of being sent, while the longest took over four hours. The average transmission time for a UK SMS is usually seven seconds.
Andy Buss, senior analyst at Canalys, said: "Intermittent outages happen occasionally for all of the networks. The New Year is traditionally one of the busiest times for SMS messaging."