You have to prorate the total cost over a 24 month period vs another large carrier (e.g. either Verizon or ATT). My guess, even with the added cost of the phone you still come out a little ahead. Again, this will vary slightly from person to person.
Ask them if you can pony up $200 instead of $99 when you upgrade to the new smartphone. That would hypothetically lower your subsequent monthly bills.
Also ask over in the T-Mobile sub-forum @ howardforums.com. A very helpful place to learn more about wireless related service/, etc.
hth
2 years ago, I got a Samsung Galaxy s2 for $200 up front, and no money after that. There was the usual FCC fees, etc. Today, I'm interested in upgrading to a Samsung Galaxy s4. However, it's $25 for 24 months, which adds up to the list price of $600! I'm told that when I was on the g2, Tmobile found a way to tack on more charges as part of its subsidies, and that since it's per month, after the contract was over, they come out on top if you did NOT renew right away. I doubt that + the upfront $200 added up to the $600 list price back then, but then again, I haven't been able to confirm nor refute that claim.
What's the best way to get subsidized discounts, or any discounts in general? Order through them online? Call them? Threaten to switch carriers?

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