The iPhone 5S and 5C will go on sale in 35 additional markets starting October 25 and another 16 on November 1, an Apple statement said.
Apple launched the new handsets last month in the United States, China and a handful of other markets, and reported nine million sold in the first three days, in the biggest iPhone launch in the company's history.
The new devices, including the lower-cost iPhone 5C, are aimed at helping Apple reverse market share losses against smartphones using the Google Android operating system, which hold about three-fourths of the market.
A November 1 launch has been set for Albania, Armenia, Bahrain, Colombia, El Salvador, Guam, Guatemala, India, Macedonia, Malaysia, Mexico, Moldova, Montenegro, Saudi Arabia, Turkey and the United Arab Emirates.
More From This Section
The new phones went on sale last month in the United States, Britain, Australia, Canada, China, France, Germany, Hong Kong, Japan, Puerto Rico and Singapore.
The new operating system has a bolder look, and includes the free iTunes Radio launched by Apple. It is a free upgrade for a number of iPhones and iPads sold in the past couple of years.