iPhone 5 preorders begin Friday at midnight Pacific, 3 a.m. Eastern

U.S. carriers Verizon and Sprint both confirmed that customers will be able to preorder the iPhone 5 starting just after midnight Pacific Time. Apple and AT&T have not yet given their preorder times, but based on years past, it's likely they will begin taking orders at the same time.

Like last year, Apple is also offering customers the ability to check their eligibility for upgrading to a new iPhone. The iPhone 5 starts at $199 when subsidized by a new two-year service contract.

Customers hoping to preorder an iPhone 5 and receive it on the launch date of Sept. 21 should probably act quickly. Last year, the iPhone 4S sold out of its launch day supply in 24 hours, after which new buyers were quoted an estimated arrival of one to two weeks.

For those who miss out on preorders, units will also be available at Apple's retail stores starting at 8 a.m. local time on the Sept. 21 launch date.

Next week's iPhone launch will be the largest ever for Apple, as the iPhone 5 will go on sale in 9 countries on the first day. A week later it will debut in 22 more nations, making a total of 31 before the end of September. Apple has said the iPhone 5 will be available in a total of 100 countries on 240 carriers by the end of December.