The Waterloo, Ont.,-based technology company plans to launch the holiday promotion in December, giving customers up to $400 of trade-in value, depending on which model of iPhone they have.
It'll also offer those who switch up to an additional $200 through a prepaid credit card.
The deep discount is only available to North American customers who order through Amazon or Blackberry's online store before Feb. 13.
BlackBerry (TSX:BB) is trying to claw its way back into the spotlight this holiday shopping season with a series of promotions that include a limited-edition Passport phone in red, a white model and alternative financing options for U.S. customers.
The company also plans to release another model, the BlackBerry Classic, an updated version of its popular older keyboard smartphones, on Dec. 17.
BlackBerry is in the midst of a turnaround plan that has involved CEO John Chen scaling back the size of the company while refocusing its priorities on corporate clients, rather than the consumer market.
However the latest round of discounts are clearly angled at enticing shoppers who will head to the malls, and e-commerce retailers, over the U.S. Thanksgiving holiday this weekend.
Whether the promotional campaign will be successful remains to be seen, said CIBC analyst Todd Coupland.
"If iPhone 6 buyers wanted a Passport they would've bought one," he said.
"You'll get some guys probably around the margin, but I'd be surprised if this has a major impact."
The Canadian smartphone maker launched the BlackBerry Passport in late September touting it as a better device for business users.
While BlackBerry hasn't released updated sales figures for the Passport, Chen said the company received 200,000 orders for the device within the first two days of its release.
Coupland suggested BlackBerry is trying to extend the initial spike in sales, which is common when a new device is released to the market.
"The predominant strategy for the company is to transition the service revenue to software revenue by managing all flavours of software devices," he added.
"If they can sell a few devices along the way, fine."
BlackBerry said the trade-in offer applies to users who have iPhone 4S, 5, 5C, 5S, and 6 models.
Shares of BlackBerry rose 12 cents to $11.88 near midday on the Toronto Stock Exchange.
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