Between February 6 and 12, Target is offering up to a $200 credit towards iPhone 4 handsets when customers trade in their old iPhones. First generation iPhones are not accepted, and your old iPhone needs to be in working order if you want to take advantage of Target’s offer.

Customers can get up to $100 off for a 16GB iPhone 3G, or up to $200 for a 32GB iPhone 3GS. Furthermore, you must take out a two year contract with AT&T when purchasing an iPhone 4, in order to receive the credit. Here’s what Target has to say regarding the offer:

iPhone 3G or 3GS trade-in – In order to take advantage of this in-store only offer, guests must trade in a working iPhone 3G or 3GS and sign a two-year contract with AT&T. Guests may receive up to $100 credit for an iPhone 3G 16GB and up to $200 credit for an iPhone 3GS 32GB, offering great cost savings on a new iPhone 4 16GB priced at $199 or an iPhone 4 32GB priced at $299.

If you’ve got an old iPhone 3G or 3GS, and are planning on grabbing an iPhone 4 with AT&T, head over to a Target Mobile and see how much you can save.

And, if you do, let us know in the comments.