For many consumers, the release of Apple's (AAPL 1.27%) new flagship brought with it a choice -- not whether to buy the phone, but which company's to buy it from. That's not as easy a decision as you might think because each company has its own pricing models, different deals, and methods of charging for the phone. That make picking between AT&T (T 1.88%), Verizon (VZ -0.53%), Sprint (S), and T-Mobile (TMUS 0.57%) a challenge.

Comparing apple to apples (or Apples to Apples)
For the purposes of comparison we're going to examine pricing based on the 16GB iPhone 6 as all four carriers start their offers with that model. Apple charges $649.99 full retail for that phone but the major carriers each find different ways to offer financing or subsidies to help consumers not have to shell out a big upfront payment.

AT&T, Verizon, Sprint, and T-Mobile also make comparing their various offers a challenge because terms like "unlimited" mean different things to different companies. AT&T no longer sells new customers unlimited plans, while Sprint has made its unlimited offer, a key marketing feature. So, when picking a plan, it's not just how the phone is financed or subsidized but what each company offers along with an iPhone 6.

The new iPhone 6 in space gray :Source: Apple

AT&T's offers
AT&T offers three ways to buy an iPhone as well as various data plans. Its "Next" plans allow customers to upgrade after 12 or 18 months, while its contract offer requires two-years between subsidized upgrades. 

The cheapest way to own an iPhone on AT&T would be using a traditional two-year contract with $199.99 upfront, plus a $40 activation fee with a small 1 GB data plan. Even if you mentally amortize the roughly $10 a month the $239.99 paid up front will cost you, it's still a slightly cheaper option than the Next 18 plan. Once you get to the higher 10 GB plan, however, both Next 12 and Next 18 are better values. 

AT&T   
Phone Next 12 Month Next 18 Month Two-year contract
Money down $0 $0  $199.99
Activation fee $0 $0 $40
Monthly fee $32.50 $27.09 $0
Cost to buy $390 $487.62  $199.99
       
Data Plans Monthly cost Monthly cost Monthly cost
1 GB  $50*   $50*  $65
10 GB $115* $115* $140
       
Monthly bill      
1 GB $82.50 $77.09 $65
10 GB $147.50 $142.09 $140

*Includes promotional savings

Verizon's offers
Verizon only offers two plans, a 24 month financing option and a two-year contract. Its prices appear good on the surface, but the company has something called "line access fees" which push up the cost of its plans.

Verizon  
Phone Verizon Edge  Two-year contract
Money down $0  $199.99
Monthly fee $27.08 $0
Cost to buy $649.92 $199.99
     
Plan    
1 GB Data $65 $80
10 GB Data $115 $140
     
Monthly bill    
1 GB Data $92.08 $80
10 GB Data $142.08 $140

AT&T's 1 GB plans are a better deal than Verizon's while both companies offer the same price on a 10 GB plan with a two-year contract though Verizon offers better financing terms with similar prices but the ability to upgrade sooner.

Sprint's offers
Sprint's core offers are its 'iPhone for Life" plan, which is a 24-month lease, where you do not own the phone but use "easy-pay" as a 24 month financing plan, and a $199.99 two-year contract plan. Sprint aggressively pushes its unlimited plans for individual (and prices accordingly) so I looked at those rather than specific data plans.

Sprint   
Phone iPhone for Life  Easy-pay Two-year contract
Money down $0 $0  $199.99
Monthly fee $20  $27.09*  $0
One-time fees $36 $36 $36
Cost to buy/lease $516  $685.99 $235.99
       
Plan      
Unlimited $50 $50 $85
       
Monthly bill      
Unlimited $70  $77.09 $85

*The fee varies slightly in the 24th month

The only price lower than Sprint's cheapest offering with unlimited data is AT&T's two-year contract offer with only 1 GB of data a month. Of course, iPhone for Life is a lease, making Easy-Pay or Sprint's two-year contract the best deals seen so far where you own your phone at the end and get a lot (in this case as much as you want) of data.

T-Mobile's Offers
T-Mobile has the least confusing pitches of any of the major carriers as the company offers no subsidies. You can either buy your iPhone for full price or finance it for $27.08 for 24 months, which is essentially the same thing just over time. T-Mobile also has a very simple data plan structure with no hidden fees. 

T-Mobile 
Phone Simple Choice
Money down $0
Monthly fee $27.08
   
Cost to buy $649.92
   
Plan  
1 GB $50
Unlimited $80
   
Monthly bill  
1 GB $77.08
Unlimited $107.08

It's also important to note that T-Mobile does not charge overage fees. Instead, it throttles down data speeds which makes its 1 GB plan more attractive.

The best overall deals based purely on price are AT&T's 1 GB of data, two-year contract offer and Sprint's "iPhone for Life" plan with unlimited data, but that deal comes with the major caveat that you're leasing not buying the phone. The other two Sprint unlimited deals are also cheaper than anything besides the AT&T 1 GB offer and the T-Mobile 1 GB plan, which is also a viable choice for low-data use customers, especially with the no-overage policy. 

If you're not a heavy data user than any carrier offers viable choices. If you want unlimited data then Sprint is your choice.