Apple: 600,000 iPhone 4 pre-orders in one day

iPhone 4 pre-orders and in-store reservations have already sold out, but just how many units did Apple expect customers to order on launch day? Far fewer than the  actual demand, it turns out.

In a statement on Wednesday about the iPhone 4 going on sale, Apple announced that it clocked more than 600,000 pre-orders for the new phone—far higher than it expected to receive:

Yesterday Apple and its carrier partners took pre-orders for more than 600,000 of Apple’s new iPhone 4. It was the largest number of pre-orders Apple has ever taken in a single day and was far higher than we anticipated, resulting in many order and approval system malfunctions. Many customers were turned away or abandoned the process in frustration. We apologize to everyone who encountered difficulties, and hope that they will try again or visit an Apple or carrier store once the iPhone 4 is in stock.

For comparison, Apple sold 300,000 iPads at launch between pre-orders and in-store sales. In its own statement, AT&T announced that first-day iPhone 4 pre-orders were ten times larger than iPhone 3GS pre-orders last year. The carrier racked up 13 million visits to its site from customers checking their eligibility for the new phone.

Apple also acknowledged that the flood of ordering traffic resulted in “order and approval system malfunctions,” leading to customers abandoning the order process in frustration. There were reports on Tuesday that, when some AT&T customers logged into the carrier’s site to pre-order, they inadvertently  gained access to different users’ accounts. Earlier on Wednesday, AT&T issued a statement acknowledging that it had received privacy complaints about the incidents, but could not replicate the issue.

Since Apple’s initial stock of iPhone 4s have been account for with in-store reservations or home delivery, Apple’s shipping dates for orders placed now have been pushed back to “by July 2”. Customers can no longer reserve a phone for in-store pickup on launch day, though Apple stores will have a limited supply of iPhone 4s on hand for walk-up customers.