Do you want a killer discount on a Galaxy S6, and do you also happen to be in the market for a new T-Mobile phone? Then today is a good day to be you. The carrier is offering $80 off of any T-Mo version of the Galaxy S5or Galaxy S6 with the checkout coupon "DEAL80OFF" (that's eight, zero, capital O, capital F, capital F). If you use the coupon with a Galaxy S6 you get a free car charger too, but we didn't have enough room to fit that in the headline.
Is that still not enough for you? Then consider the following: the top-of-the-line 128GB version of the Galaxy S6 is currently on sale for $659.99, the same price as the 64GB model. Add in the coupon and you get an extra $80 off, for a final price of $580, a savings of $280 off of the retail price. Plus a free car charger. Not bad at all.
T-Mo is probably offering the discount to move some stock - the S5 is getting long in the tooth (at least by the insane standards of flagship smartphones), and I imagine it's getting harder to move the Galaxy S6 with the newer S6 Edge+ and Note 5 available. Heads up: these deals may or may not be available to existing T-Mobile subscribers - I don't have an active account, so I can't test them.