The initial supply of phones went on sale online just after midnight. Within 10 minutes, the gold option had a ship date of 7 to 10 days. By a half-hour in, the back-order date was in October. The wait is for all three storage options offered: 16 GB, 32 GB and 64 GB.
Supplies of white and gray iPhone 5S models have lasted longer, presumably because they are similar to colors already available for the iPhone 5. Some of the models are still back-ordered, though, but just for seven to 10 days.
Apple has asked suppliers to increase production of the gold 5S to meet demand in the U.S. and abroad.
The gold has been the most popular option in stores, too. In Apple's Santa Monica location, the first 14 customers picked up the only remaining gold iPhones. At one of the store's New York locations, the fourth person in line was notified she would not be able to get one in gold. The Toronto store at Eaton Centre sold out of gold iPhone 5Ss before the store even opened.
The phones could be the biggest consumer electronics launch in history, said Carl Howe, vice president for research and data sciences at the Yankee Group.
Howe predicts 12 million units sold from launch to the end of the month, assuming Apple can keep up with the demand.