If you’re an AT&T subscriber looking to upgrade to a new iPhone before the end of the year, you’re in luck. MacRumors discovered this week that AT&T is offering a $50 bill credit to anyone who purchases a new iPhone from the Apple Store, whether you’re shopping online or at a retail location. Oddly, neither Apple nor AT&T are advertising this deal publicly.

There are a few stipulations worth noting, so be sure to read ahead for more information.

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In order to qualify for the promotion, your new iPhone must be purchased on a pre-existing line as an upgrade, it must be paid for with AT&T Next and it has to remain active and in good standing on Next for at least 45 days.

This is the text that appears at checkout to indicate that you can take advantage of the promotion:

$50 Bill Credit Offer: Ends 12/31/14. Must remain in active and in good standing on Next for 45 days to receive bill credit on your AT&T mobility bill within 3 bill cycles. Upgrades only. Requires iPhone to be purchased via AT&T Next and activated on a qualifying AT&T voice and data wireless service plan. Offer may not be combinable with other credits, discounts and offers. Offer and terms subject to change and may be discontinued at any time without notice.

MacRumors notes that although this is scheduled to last until December 31st, AT&T can discontinue the promotion at any time.

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